How Vinci shocked Williams

1. Federer thrashes Wawrinka 6-4 6-3 6-1 to reach Sunday's final
2. Djokovic beats Cilic 6-0 6-1 6-2 in first semi-final
3. Roberta Vinci stuns Serena Williams in women's semis
4. Unseeded Vinci ends Williams' hopes of calendar Grand Slam
5. Fellow Italian Flavia Pennetta beats Simona Halep 6-1 6-3

Goodbye

Robotic, indefatigable, top seed Novak Djokovic?

AP

Or the smooth, majestic, 17-time Grand Slam winner Roger Federer?

Getty Images

Anyone dare to call Sunday's US Open final? Nope, me neither. Although I'll let you into a not-so-secret bit of info - Federer leads 21-20 in the head-to-head against his great rival.

Make any difference? Probably not. But it gives you a little something to occupy your mind when thinking about the outcome.

Right it is time for us to say goodbye. We will be back tomorrow for the women's final and of course will return on Sunday. See you then!

Player reaction

Roger Federer:  "Novak has had a tremendous year, there's always a lot on the line when we play. He's the best mover on the hard courts, he's tough mentally, but I like that challenge and I'll be ready for it.

"Serena has done unbelievably well, maybe it just wasn't meant to be. We're lucky that she's still playing tennis."

Get involved

Liam Walton:  Federer is just unbelievable. Even at the age of 34, he makes it look so easy! Class is permanent.

Player reaction

Roger Federer:  "Obviously I am very happy. It's been a great tournament so far - I have tried so hard over the last six years to the get back into the final, and tonight it worked. 

"I'm serving very well, I'm going for my shots, I'm playing positive tennis. I practised for years in front of nobody, I'm not going to throw away moments like this."

Federer reaches US Open final

Stan Wawrinka trudges off court looking slightly shellshocked - he has been hit by the Fed Express. Rather like Marin Cilic before him, he didn't have the opportunity to lay a glove on his illustrious opponent. The two Swiss men warmly embrace at the net - I don't think I could be so gracious to someone who has just thumped me in front of 20,000 people.

Stan will move up to fourth in the world rankings after this tournament. Scant consolation.

Federer reaches US Open final

That routine win - which has taken just 92 minutes - means second seed Roger Federer will meet top seed Novak Djokovic in Sunday's final. I think those two are quite familiar with each other....

Russell Fuller

BBC tennis correspondent on Radio 5 live Sports Extra

"You run out of superlatives. There is nothing that Stan Wawrinka can do to stop the Roger Federer juggernaut rolling artistically onward."

Jeff Tarango

Former professional tennis player on BBC Radio 5 live Sports Extra

"The fans are on their feet clapping as if Federer has just finished a concerto."

Game, set and match - Federer

Reuters

Wawrinka threatens to make Federer wait at 15-30, but then again has no answer to Federer. That brings up match point - and a huge roar of anticipation from the Ashe crowd. Wait - Stan isn't going without a fight. A trademark backhand winner down the line makes Roger hold on.

But not for long, Federer tees up a second match point - and blasts an ace down the middle. Job done.

So here we go. With less than 90 minutes on the clock, Roger Federer is serving for the match....

Federer breaks

We think we've cracked what is making Roger Federer so difficult for Stan Wawrinka to get near. Not the dreamy forehands or sensational serves. Not the precision punches or his anticipation. Nope, it is the eye-squinting colour of neon pink trainers. Poor old Stan's sight is being dazzled.

Of course we jest - Federer has been simply off the scale. As illustrated as he racks up another break point. Wawrinka tries every plan of attack that he has, but Federer's defence holds firm as they trade blows in a long rally. And it is the fifth seed who crumbles first, slapping a frustrated forehand into the net.

Jeff Tarango

Former professional tennis player on BBC Radio 5 live Sports Extra

"Federer is really in the zone. He looks really mentally fresh. He's getting more sleep now, because his kids have grown up a little."

Russell Fuller

BBC tennis correspondent on Radio 5 live Sports Extra

"It's almost like Federer is in a race with Novak Djokovic. This goes down as more impressive. It's a remarkable demolition."

Following up the break of serve with a booming ace is exactly what Federer could have hoped for. And that's exactly what he gets. That sets the platform for a comfortable hold - save for a stray backhand for 40-15 - and leaves Federer two games from yet another US Open final.

Federer breaks

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How important could this point be? A match winner for Federer? Quite possibly. The game is delicately poised at 30-30 as the pair become embroiled in a baseline shootout. Duh duh duh...Wawrinka blinks first to hand a break point to Federer. And another unforced error from Wawrinka - this time going long - puts Fedrer on course to wrap this up quick sharp.

Federer is purring like a cat which has just devoured a saucer of the finest cream on the planet. His smooth serve peppers the Wawrinka defence, finishing off his rival with a forehand smash.

Solid hold from Wawrinka, allowing Federer just the one point. Unfortunately solid holds alone aren't going to stick the fifth seed in the US Open final. He needs a breakthrough....

Thanks James. During the changeover Wawrinka would have been sat in his chair, dreaming of a morale-boosting break at the start of the third set. A rare double fault from Federer gives him a whiff of one at 40-30, but then slams the door shut on his Swiss compatriot. Stan is not the man as his usually faultless backhand crashes into the net.

Here's Jonathan Jurejko to take you through to the conclusion...

Federer wins second set

Wawrinka is under siege. This is a man who has won two Grand Slam titles and he quite literally doesn't know what to do. Such is Federer's brilliance, he's reduced to trying impossible winners and hopelessly over-ambitious trick shots. 

He balloons a forehand long to bring up 0-40 and three set points. Federer needs only one. A seventh US Open final is in sight.

Jeff Tarango

Former professional tennis player on 5 live sports extra

I'm not sure what I like more - a nice cup of chocolate mousse or watching Roger Federer win so smoothly. It's delectable.

*Wawrinka 4-6 3-5 Federer

This is glorious, artistic tennis from Federer. He's going through the whole repertoire at the moment. When Wawrinka tries to put a smash into the empty court, Federer is there. When Wawrinka tries to lob him, Federer somehow scrambles back and manages to flick it disdainfully back past him. Wawrinka can't lay a glove on him.

Russell Fuller

BBC tennis correspondent

It is going to be so tough for Stan to keep having to save break points. All the momentum is going against him at the moment.

Federer breaks

The scoreboard might be all square - but there's no doubt who is under the more pressure. A mishit from Federer forces Wawrinka back, and suddenly he's in trouble again at 0-30. Stan goes long and Federer has three break points. Wawrinka fires long again, and Federer is in charge in the second set.

*Wawrinka 4-6 3-3 Federer

The Federer serve is well and truly firing. The ball toss, the arch of the back, the rapid arm all flowing in one seamless movement - the ball more often than not kissing the corner of the service on its way past Wawrinka. If that doesn't work, saunter to the net and poke a volley past Stan. Easy peasy.

Russell Fuller

BBC tennis correspondent on 5 live sports extra

Most players are used to hearing the crowd supporting Roger Federer. Poor old Stan. Novak Djokovic might even have to face the same on Sunday.

Wawrinka 4-6 3-2 Federer*

If Federer was a boxer, he wouldn't just have quick hands and a pretty left hook, he'd also be adept at soaking up punishment. He rides a couple of huge groundstrokes from Wawrinka and loops a big forehand winner into the corner.

Wawrinka sends a simple volley into the net and it's break point Federer. A big serve comes to Stan's rescue. Then it's another pistols-at-dawn point at the net, with Federer emerging victorious with a volleyed winner.

Another break point, but Stan closes it out with a good volley of his own, which he follows with a bellowed 'Come on!' Two big serves, and he's in the clear.

*Wawrinka 4-6 2-2 Federer

Wawrinka garnered a lot of attention during the French Open for wearing shorts that were more garish than a hippie's tablecloth, but disappointingly, he's bedecked in a crisp white pair today.

Federer rattles through another brisk game, scooting to net to punch away a couple of volleys. We remain on serve.

Jeff Tarango

Former professional tennis player on 5 live sports extra

Stan is trying to overpower Roger but he needs to use that slice to set up shots that he can rip winners off with. And he needs to see when Roger is sneaking in on the run. He has a great passing shot - he's just not utilising it yet.

Wawrinka 4-6 2-1 Federer*

Federer tries to charge the serve again, but this time he finds the net. A booming backhand down the line takes Wawrinka to 40-0, and Federer coughs up the game when he nets a forehand.

*Wawrinka 4-6 1-1 Federer

Bradley Cooper is in the audience. So far today we've seen him, Sean Connery and Canadian rapper Drake, which coincidentally is the line-up for my dream dinner party.

Talking of dreams, Roger Federer's serve is pretty dreamy - he finds the corners with pinpoint accuracy for an impressive hold to love.

Jeff Tarango

Former professional tennis player on 5 live sports extra

In the first set Stan had break points on the opening game of Federer's serve and didn't break. In this set, Federer had a break point and didn't break. But Federer turned around in the next game and broke. Let's see if that pattern continues.

Wawrinka 4-6 1-0 Federer*

Wawrinka, by the way, is yet to beat Federer on hard courts - he's 0 for 8, as the Americans say. This is a must-win set for the fourth seed.

A double-fault and a typically picturesque leaping forehand from Federer take him to 30-30, and he opens up the court masterfully to give himself a forehand down the line for break point.

Terrific response from Stan, bludgeoning an inside-out forehand into the corner. Two big serves complete the escape act, and that's a big hold.

Get involved

John McEnerney:  Fed looking majestic but Stan is no slouch this hopefully will go the distance after that walkover by Novak. Federer in four.

Sara Orchard

BBC Radio 5 live sports extra commentator

The style Roger Federer is playing is so exciting, so different and Stan hasn't found a reply.

Federer wins first set

Now look, I'm a modern man, in touch with my feminine side and all that, but I'm not sure I'd be too comfortable wearing the Federer get up down the local municipal courts. White polo with pink collar and piping, shorts with pink piping, pink wristbands and pink trainers. It's...zingy.

Still, it's not doing Federer any harm out there - a slightly too aggressive Wawrinka sends some potent groundstrokes over the baseline and into the net to bring up two set points. Another forehand flies long from Stan, and that's the set.

Jeff Tarango

Former professional tennis player on 5 live sports extra

Stan's first serve percentage is only 39%. He needs to change up his first serves with some serves that he knows 100% will go in and it will also keep Roger off balance. When Roger locks into a shot you're hitting to him repeatedly, you're done.

Wawrinka 4-5 Federer*

One thing Federer has been brilliant at over the years is sending the ball about a gnat's width over the net with the velocity of a speeding asteroid - Wawrinka comes to net to dispatch a volley but suddenly finds the ball at his bootlaces and can't get it over the net. 30-30.

Stan again targets Federer, sending a smash straight at him to bring up 40-30, and he closes the deal. Fed will serve for it.

Jeff Tarango

Former professional tennis player on 5 live sports extra

Federer is changing his racquet for a third time - I think he wants a tighter racquet to respond to Stan's serve.

*Wawrinka 3-5 Federer

Now, I know the Swiss are a peace-loving nation. And yes, yes, these two are great pals, yadda yadda. But if my imagination doesn't deceive me, Stan is going for Roger here. He's trying to foil Fed's sneaky tactic of rushing to net with the not-so-subtle strategy of absolutely leathering the ball at him when he gets there.

It works as he almost takes the racket out of Roger's hand, bringing up 15-30, but Federer gets himself out of trouble with three straight points.

Jeff Tarango

Former professional tennis player on 5 live sports extra

That was a sick volley and unreal get by Federer - I actually thought he had won the point.

Wawrinka 3-4 Federer*

Oh my word. Wawrinka looks to be cruising at 40-15, but he sends a forehand long. Can Federer get to deuce? Wawrinka absolutely nails a smash at 40-30, but Federer, inescapable as time, is there, somehow, and absolutely pings it right off the strings about an inch over the net. Stan is equal to it though and nonchalantly knifes the volley into the open court. That is what Alan Partridge would call liquid tennis.

Jeff Tarango

Former professional tennis player

That charge forward and volley from Roger Federer was reminiscent of his coach Stefan Edberg - that's why I've been calling him Fed-berg.

*Wawrinka 2-4 Federer

Federer's usual gossamer touch deserts him at the net as a drop volley sits up for Wawrinka to smack a passing winner past him, and suddenly Stan has 0-40 and three break points.

Federer saves the first two with an ace and a putaway, and he fends off the third with a display of real cojones - following a second serve into the net and painting the sideline with a volley. He closes out a Houdini-esque hold with an ace.

Wawrinka 2-3 Federer*

That'll make Stan feel better - absolutely torching a backhand winner past Fed to get to 40-0. That one left scorchmarks on the court. Federer then dumps one into the net and Wawrinka remains in touch.

Jill Craybas

Former world number 39 on BBC Radio 5 live sports extra

It was important for Federer to get on top early in the match - that is how he has won a lot of his matches. That is a huge break.

*Wawrinka 1-3 Federer

Federer may be 34, but there's still some elastic in that serving arm - the ball is clearing the spectators in the first row as it bounces past the flailing Wawrinka. A couple of howitzer deliveries help Federer to a love hold.

Federer breaks

Now then, here's the Roger Federer sneak attack that we've been hearing so much about. In case you haven't keeping your ear to the tennis grapevine, Fed has caused a few ripples by charging into the net to take his opponent's serve halfway up the court. It fails the first time, by on the next point it works and Wawrinka nets.

The tactic clearly unsettles Wawrinka and he pings a forehand off the tape and into the tramlines to bring up break point. Wawrinka sends a forehand long, and it's first blood to Federer.

*Wawrinka 1-1 Federer

On 5 live, Jill Craybas reckons that you can tell by the way Stan uses his walk, he's a US Open contender, no time to talk. Or words to that effect. He certainly carries a bit of a spring in his step.

But then again the man across the net, resplendent in pink sweatbands today, has never been known for a lack of confidence either. Federer fends off a minor hiccup at 30-30 with a good approach, but then Wawrinka stings him a crisp one-hander down at his toes. Deuce.

Fed sends one into orbit off the frame, and suddenly he's staring down the barrel of a break point. Stan shanks the return, and then sees an ace whizz past him at nostril height. Wawrinka sends a backhand long, and Rog is on the board.

Get involved

Christopher David:  Currently contemplating how long I stay up to watch this undoubted classic Federer/Wawrinka match.

Wawrinka 1-0 Federer*

Woof. Plenty of mustard on the Wawrinka serve, and he's up and running with a simple hold.

Here we go. It's Wawrinka to serve first...

BBC Sport

Swiss spat

But then again, he's got a formidable obstacle in his path: Stan Wawrinka, undoubtedly the most improved player on tour over the past couple of years.

These two have had a complicated relationship. For many years, they were great friends, enjoying some great times together, including winning gold at the 2008 Olympics.

But the Swiss neutrality was rather soured last year when Federer and Wawrinka had a spat at the ATP Tour Finals, apparently sparked by Mrs Federer calling Wawrinka a "crybaby".

The two of them thrashed it out in the locker room, we're told. But who knows, if this one goes the distance, is it too much to hope it could get a little bit spicy?

BBC Sport

Fabulous Fed

Let's begin with a consideration of Roger Federer - a man who has used up all the superlatives in the dictionary, and all the space on his mantlepiece over a glittering 16-year career.

You keep waiting for Federer to lose it. To enter a terminal decline. But no, at 34, he seems to be playing better than ever. Heck, he's won his last 35 sets. Could he finally clinch his 18th Grand Slam? You wouldn't bet against it...

Thank you JJ. Well, what a strange day it's been at Flushing Meadows. Simona Halep taken to the cleaners. Serena Williams losing from a set up against the world number 43. And now, the defending men's champion booted out the back door on the back of the most one-sided semi-final in the Open era.

What surprises might Federer v Wawrinka have in store? We wait to find out...

So the identity of one US Open men's finalist is known. But who is the top seed going to face? One thing is certain - it will be a Swiss fella.

Good job that the Alpine nation is well-known for being a 'neutral' country as two of their stars scrap for a place in the Flushing Meadows final.

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Here's my team-mate James Gheerbrant to talk you through all things Swiss....

Djokovic reaches US Open final

As if the scoreline doesn't already tell you everything, here are a few more numbers to make Marin Cilic wince. The key stat being that Cilic made 37 unforced errors compared to Djokovic's 13. And the top seed won 87 points in total, dwarfing the 39 earned by Cilic.

Player reaction

Novak Djokovic:  "I'm very proud to have reached all four Grand Slam finals. I haven't been very successful in the finals of the US Open - I have won one and lost four. But I can promise I will give it my best. I will definitely get ready to play against a Swiss player!

"Serena is a great champion, she is somebody I respect a lot, it wasn't to be today but it takes nothing away from what she has achieved in her career."

Player reaction

Novak Djokovic:  "Marin was carrying an injury, he was courageous to come out and finish the match, so applause to him. 

"I came out with good focus and good intensity and executed the gameplan."

Djokovic reaches US Open final

Novak Djokovic is grinning like a Cheshire Cat as he addresses the Arthur Ashe Stadium after that routine win. He admits he is hoping to rectify his poor record in the Flushing Meadows final - winning one and losing four - on Sunday. There he will face one of Swiss pair Roger Federer or Stan Wawrinka who are next on the star-studded US Open bill.

Jill Craybas

Former world number 39 on BBC Radio 5 live Sports Extra

"It's a shame - Cilic obviously isn't feeling 100%. He fought his hardest, but he couldn't move today, he couldn't give his best."

It is hard not to feel some sympathy for Marin Cilic. Novak Djokovic made him look like a club player rather than a Grand Slam winner. Although, as Novak graciously points out in his on-court interview, the ninth seed has been struggling with an ankle injury over the past couple of matches. Did that have a part to play in Cilic's no-show? Probably - sure we will find out more about that a little later on.

Game, set and match - Djokovic

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Stunning stuff. Novak Djokovic brings an overhand backhand smash to the party, giving himself three match points. Second serve....Cilic returns....Novak plants a forehand into the net. One down. But Cilic coughs up the second, a long baseline rally ending when the Croatian clunks a forehand long. He couldn't wait to escape from Ashe....

Djokovic breaks

Don't you hate those people who say 'I told you so'? Well, I told you so. Novak Djokovic does not look like he needs two service games to see of Marin Cilic. More errors from the Croatian gift three break points to Djokovic, who snaffles the first one. The record for the least number of games lost in a US Open semi-final? Four. And that came in 2001 when Lleyton Hewitt beat Yevgeny Kafelnikov...

Novak Djokovic is two service games away from his sixth US Open final - and it might not even take him that long. Cilic takes the first point in game eight of the third set, only for the Serb to wipe that out with an ace before going on to clinch the hold without further damage.

David Law

BBC Radio 5 live Sports Extra commentator

"Cilic is giving everything he's got. He's not short-changing the fans at all. But they are watching a masterclass from Djokovic."

Djokovic breaks

Reuters

Beware the wounded world number one. Cilic's break in the last game was only the eighth time that Djokovic has not held his serve in this tournament - and he didn't like it. He goes on the attack against the Croatian, teeing up two break points and nabbing the first one. As you were...

Cilic breaks

Cilic glances up towards the scoreboard at 30-15 - don't do it, Marin. He looks dazed and confused - rather like a man who has been released into everyday society after a period of captivity.

But the stark realisation of the numbers do seem to jolt him into life. A brilliant forehand winner helps him tee up a break point. Yes, you have read that right - Marin Cilic has a break point. And he takes it!

High-quality stuff from the defending US Open champion, whose neat dropshot is even too much for Djokovic to rescue. A bald gentleman wearing a Croatian football shirt and red and white paint on said follically-challenged cranium claps heartily - as does the rest of Ashe.

Jill Craybas

Former world number 39 on BBC Radio 5 live Sports Extra

"That was a better game from Cilic. He's still struggling, but at least he tried to play the right style of tennis: big serve and big forehand."

Marin Cilic manages to salvage some pride with his best service game of the evening. And he even manages to cook up a double fault in this. The Croatian cruises into a 40-0 advantage with an ace, has a little wobble with a couple of shocking serves, then regains his composure to win the game with a crunching forehand down the line.

David Law

BBC Radio 5 live Sports Extra commentator

"In this sort of form, Novak Djokovic is going to take some stopping at this US Open."

AP

Move along, nothing to see here. Apart from more Djokovic brilliance that is. The top seed holds out to love again, sealing the game with a scrumptious lob that a scrabbling Cilic manages to reach but can't stick back over the net.

Djokovic breaks

Anyone giving Cilic any chance of winning a set? The most optimistic - or sympathetic - fans might have done about one minute ago - not now.

The Ashe crowd try to gee up Cilic after he bangs an ace down the T for 15-30, before Djokovic curses himself for overcooking a backhand down the line. Chill out Novak, you're coasting.

Luckily Cilic is feeling charitable today, handing over a break at the first opportunity.

Jeff Tarango

Former professional tennis player on BBC Radio 5 live Sports Extra

"Cilic should pull the plug. There's nothing Goran Ivanisevic can say to him to spark him into life."

David Law

BBC Radio 5 live Sports Extra commentator

"You've got to give Djokovic massive credit. He is so tunnel-visioned about what he wants to do. He's a great friend of Marin Cilic but that counts for nothing."

Game and second set - Djokovic

Incredible. Wonderful. Clinical. Insert any other superlative of your choice. Djokovic gives the tiniest whiff of hope to Cilic at 30-30, before snatching it out of his hands with a second ace of the match and an aggressive forehand down the line. Cilic doesn't know what day it is.

Double break for Djokovic

AFP

If this was a boxing match then the referee would be stepping in. Djokovic earns another break of the Croatian's serve - now he is serving for the second set. Cilic goes 30-15 up and then pulls out a 106mph second serve which Djokovic duly spanks a blistering crosscourt forehand. Wow. That knocks the stuffing out of Cilic, who meekly surrenders the final two points.

Novak Djokovic is rattling through his service games quicker than a comedian goes through one-liners. But Marin Cilic isn't laughing. Djokovic generously allows Cilic a first point of the second set against his serve, only for the Croatian to repay the favour with another unforced error - a lazy forehand into the net - to seal the game in the Serb's favour.

Jeff Tarango

Former professional tennis player on BBC Radio 5 live Sports Extra

"I think Goran Ivanisevic [Cilic's coach] might get up and walk out. I'm not sure what's going on inside his head right now - I imagine it looks like a lava fireball."

Djokovic breaks

Stop the clock! We're 42 minutes into this, ahem, contest and we see our first poor shot from Novak Djokovic. The Serb looks to the heavens as he plants a weak forehand into the net at 30-15. But soon it is Cilic grimacing again. Another break point to Djokovic when the Croatian crumbles after a long baseline rally, then another forehand unforced error gifts the first break of the second set to the world number one.

David Law

BBC Radio 5 live Sports Extra commentator

"It's almost as if Cilic isn't in the right place for some of these shots. His footwork isn't dynamic enough."

Reuters

How would 007 get out of a scrape like this? With some smooth talking and a cunning escape plan probably. Let's hope Marin Cilic, who sees another Djokovic service game to love flash past him, has got the latter. If not then he might want to grab a quick word with Sean Connery at the changeover. A Cilic comeback? Never say never, again...

The person who is operating the Cilic side of the scoreboard had better wake up. We need him. The Croatian finally sees a number go next to his name when Djokovic misses the target by a matter of millimetres with a crosscourt forehand. Huge cheers (maybe some ironic) from the Ashe crowd...

Any chance of Novak Djokovic easing off? Nope. The Serb tees up another break point with some unreturnable returning, although Cilic saves that with a handy first serve which is too hot for Djokovic to handle.

But another unforced error from Cilic - a long backhand under little pressure in a routine rally - sets up a second break point for Djokovic.

Again Cilic scrambles the game back in his favour, setting up his first game point of the match - in the EIGHTH game. However, he cannot convert...

Jeff Tarango

Former professional tennis player on BBC Radio 5 live Sports Extra

"This is starting to look like clean up on Aisle Six."

This is X-rated stuff from Novak Djokovic. The match needs a 'Parental Advisory' warning - it is a brutal assault on Marin Cilic. The Croatian has no answer to the Serb's service game, which is over to love in almost a blink of an eye.

Jeff Tarango

Former professional tennis player on BBC Radio 5 live Sports Extra

"Cilic has won 15% of second-serve points, and he's only got 41% of his first serves in. You've got one player who's fresh as a daisy and another guy who's at the end of his string: that's why it's lopsided."

David Law

BBC Radio 5 live Sports Extra commentator

"It's difficult to think how Cilic can even make a fight of this, the way it's going. There's about 20,000 people in here and they're getting nothing like a contest - you can hear a pin drop."

Game and first set - Djokovic

Unbelievable stuff. Djokovic misses a second set point - but makes no mistake with a third. The top seed's movement has caused all sorts of bother for the ninth seed, who crumbles in just 24 minutes.

AP

Oh dear. Marin Cilic almost knocks out a ball boy with a wild swipe that is nearer the spectators' gangway than the tramline as he goes 15-0 down.

A decent first serve is a confidence booster if nothing else - as is a humdinger of a serve which flashes past Djokovic's eyeline for his first ace of the match.

But another unforced error from the baseline hands another break point to Djokovic. The Croatian pulls out a beautiful dropshot that floats over the net and touches white paint. Deuce...

Novak Djokovic holds comfortably to 15 and then gives his face a good rub with his towel as he sits back down. I don't know why - he has hardly broken sweat. Marin Cilic, on the other hand, will be feeling rather nervous. Apparently he has only been bagelled once this year. His opponent? The bloke staring across the net from him. Novak another break of serve away from the first set....

Jeff Tarango

Former professional tennis player on BBC Radio 5 live Sports Extra

"Cilic isn't setting up very well. The little adjustment steps with his feet just aren't there. He's not assessing the shots well, and Novak's varying his serve, so Cilic isn't timing it that well."

Double break for Djokovic

Wow. Cilic thinks he is on the attack, whipping a forehand down the line. But Djokovic turns defence into offense quicker than Barcelona's football team. A wonderful winner down the line leaves Cilic's coach Goran Ivanisevic looking glum, although the former Slam winner's expression becomes cheerier as his man battles back to 30-30.

Cilic looks to get on top in a long rally, pounding a forehand into the corner. But Djokovic pulls a double-handed backhand out of the top drawer, forcing Cilic to volley into the net. Another break point. And then Cilic crumbles. Double fault from the ninth seed hands the game to Djokovic on a silver plate.

Marin Cilic is already wearing the expression of a man who knows he has a tough shift ahead of him. Cilic clubs another forehand long for 0-15 and, after being handed a point by a wayward Djokovic forehand, soon finds himself back in his seat without a sniff of a break.

Novak asks the umpire if the floodlights are going to be switched on soon. I'd have thought his coach Boris Becker - wearing a luminous orange t-shirt - is already providing enough light to illuminate Ashe.

Jill Craybas

Former world number 39 on BBC Radio 5 live sports extra

"This is not the best match-up for Cilic. He's got the game to beat Djokovic, but Djokovic just does everything a little bit better. He has to try and tee off to beat someone like Djokovic, but sustaining that is pretty tough to do."

Djokovic breaks

EPA

Right then Marin - what has your service game got to offer? Not much initially, although that is more to do with Djokovic's fine retuning than anything else. Djokovic, decked out in a Birmingham Cityesque blue polo shirt with white collar, scrambles to force Cilic into a weak volley into the net from point-blank range then tees up a triple break point.

One goes begging as Djokovic is unable to return a deep forehand from the baseline. Then the Serb sees another disappear into the net. But he is not to be denied, a long rally ending in the top seed's favour when Cilic goes long down the line.

Jeff Tarango

Former professional tennis player on BBC Radio 5 live Sports Extra

"Cilic has got to go for it. He can't be intimidated by Novak's groundstrokes, he can't be afraid to come in."

Here we go. Djokovic has the hour of serving first - and earns a quick hold.

A 102mph second serve out wide sets the tone from the top seed, Cilic unable to control a wild forehand return. The Croatian hammers another forehand wide, before Djokovic bangs down another hot second serve as Cilic backhands into the net.

Then, a blistering ace from Djokovic seals the deal. Impressive.

* denotes next server

BBC

Jeff Tarango

Former professional tennis player on BBC Radio 5 live Sports Extra

"Serena is so reliant on her athleticism, and I think her coach is a little bit at fault. She had no plan B and plan C. You can bet that Djokovic and Federer and Wawrinka have at least three gameplans."

"One minute," growls the umpire. Both Djokovic and Cilic - who has smashed down more aces than anyone else at the tournament - hammer a few serves across the net before retaking their seats. Almost showtime....

BBC Radio 5 Live Sports Extra

Novak Djokovic on Serena Williams: "It's a sport, it happens. She is a player who expects a lot from herself, but sometimes it is not your day. 

On his match: "This surface suits Marin and obviously he will step out and be aggressive."

Cilic's route to the semi-finals

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Quarter-finals: 19 Jo-Wilfried Tsonga (France) 6-4 6-4 3-6 6-7 (7-3) 6-4

Last 16: 27 Jeremy Chardy (France) 6-3 2-6 7-6 (7-2) 6-1

Third round: Mikhail Kukushkin (Kazakhstan) 6-7 (5-7) 7-6 (7-1) 6-3 6-7 (3-7) 6-1

Second round: Evgeny Donskoy (Russia) 6-2 6-3 7-5

First round: Guido Pella (Argentina) 6-3 7-6 (7-3) 7-6 (7-3)

Djokovic's route to the semi-finals

Reuters

Quarter-finals: 18 Feliciano Lopez (Spain) 6-1 3-6 6-3 7-6 (7-2)

Last 16: 23 Roberto Bautista Agut (Spain) 6-3 4-6 6-4 6-3

Third round: 25 Andreas Seppi (Italy) 6-3 7-5 7-5

Second round: Andreas Haider-Maurer (Austria) 6-4 6-1 6-2

First round: Joao Souza (Brazil) 6-1 6-1 6-1

Here we go. The players have arrived on Ashe, with Marin Cilic walking out first. A warm round of applause greets the Croatian before a bigger roar welcomes Novak Djokovic. Both players stick an arm around each at the net as the bring out their best smiles for the snappers. The sound man fails miserable at the coin toss - my straining ears think they heard Cilic win the toss...

BBC

Meanwhile, the ever-cool Roger Federer strolls into Flushing Meadows as he clambers out of a dark-windowed people carrier. Little fanfare as the 17-time Slam champion slowly walks in - dipping into his pocket to pull out his accreditation.

Television pictures show us an aerial view of the sun setting over the Big Apple. Lovely stuff. But we'd rather be sat in Salford - honestly. Hopefully we will soon see images of Djokovic and Cilic striding out onto Ashe rather than the Gotham skyline....

Game, set and match

Reuters

While a murmur of anticipation rumbles around the cavernous Arthur Ashe Stadium ahead of Djokovic v Cilic, the noise volume over on Louis Armstrong Stadium is considerably higher.

Because there we have just seen Martina Hingis - the Swiss comeback queen - continue her remarkable reinvention as a doubles specialist in the mixed doubles alongside Leander Paes.

Hingis and Paes have beaten American pair Bethanie Mattek-Sands and Sam Querrey in the final, making them the first team since 1969 to win three Grand Slam titles in the same year.

Tale of the tape

BBC

'A state of shock'

Piers Newbery

BBC Sport at Flushing Meadows

"With Djokovic and Cilic preparing to emerge from the locker room for one of the biggest matches of their year, even career, it is fair to say they will have to come up with something pretty special to garner much attention. Flushing Meadows remains in a state of shock after Roberta Vinci, currently beaming her way through a lengthy press conference, beat Serena Williams, currently enduring the Friday afternoon New York traffic. 'This is monumental,' former champion Tracey Austin tells BBC Sport. 'It's a shocker. This is one of the biggest upsets in the history of tennis, because of what was on the line.'"

Get involved

How much of a shock was Serena Williams' earlier defeat by unseeded Italian Roberta Vinci? Vinci's admission that she never dreamed that she would beat the top seed tells you.

And former American player Jeff Tarango - now working for our colleagues on BBC Radio 5 live sports extra - reckons it is "one of the biggest sporting upsets ever". Now, our Jeff is a man not afraid of a hyperbolic statement, but it has got us thinking. What is THE greatest sporting upset?

You know the drill. Tweet #bbctennis or text 81111. Come on, let's be 'aving you!

Recovered from our first instalment of gripping tennis yet? Good. And if you are only just arriving to the party then you've missed one heck of a shocker. No, your ex-partner hasn't turned up with a new squeeze - hot favourite Serena Williams has been dumped out of the women's semi-finals.

Empics

How's the rest of the night going to pan out? We're about to find out. First through the door at Arthur Ashe Stadium - in about 10 minutes - are Novak Djokovic and Marin Cilic. And the all-Swiss battle between Roger Federer and Stan Wawrinka follows that match.

Good job it is a Friday night - you've got no excuse not to stay up.

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Four Grand Slam winners. Two spots in the men's singles final. It doesn't take a mathematical genius to work out that equation.

Either world number one Novak Djokovic or defending champion Marin Cilic will be heading home tonight.

And then they might see either Roger Federer, the 17-time Slam maestro, or French Open champion Stan Wawrinka going through security at JFK Airport in the morning.

Welcome to Semi-final Day Part II.

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The Fab Four are going through their final preparations before heading on stage at Flushing Meadows. Tightening their strings, limbering up, perhaps stretching their vocal chords.

It was 50 years ago today (almost) that John, Paul, George and Ringo taught New York how to play.

But tonight, just a thumping volley across Flushing Meadows from the now-demolished Shea Stadium where The Beatles played their biggest and most iconic gig, four more blokes are hoping to whip the American crowd into a ear-splitting frenzy. And there is not a mop-top in sight.

Ladies and gentleman, here is tennis' very own Fab Four...Novak, Marin, Stan and Roger.

Veni, vidi, Vinci

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Against the odds, Italy's Roberta Vinci came saw and conquered against the world number one and 21-time Grand Slam champion Serena Williams.

Can the men top that? They'll have to go some, but make sure you join us for Novak Djokovic v Marin Cilic and Roger Federer v Stan Wawrinka at 21:45 BST. Until then, arrivaderci.

Getty Images

So, a 33-year-old faces a 32-year-old in the women's final, and we're about to have the mixed doubles final, featuring 34-year-old Martina Hingis and 42-year-old Leander Paes.

Is there any hope for us young folk?

Quiet please, ladies and gentleman. The United States' tennis-loving first lady, Michelle Obama, has spoken...

Who's your money on for tomorrow then? Two first-time Grand Slam finalists, the world number 26 against the world number 43.

Pennetta will probably start as favourite, and she leads the head-to-head 5-4. But who would bet against Vinci in this form?

Getty/ Reuters

Get involved

James Gallagher:  Vinci's an instant star after that match and post-match interview!. Sorry for Serena, but that's entertainment.

Curt would be a generous description of that press conference from Serena Williams. She's clearly eager to get it over and done with. But to her credit, she remains professional with the media.

Player reaction

Serena Williams: "She played out of her mind. I don't think I played that bad - made a few more unforced errors - but she played really well.

"I don't feel pressure, never feel pressure and never felt that pressure to win here. I said that from the beginning.

"I made a couple of tight shots - about two - but that is normal in any match for me."

Reuters

'I don't want to talk about it'

Serena's doing her press conference now.

"I don’t want to talk about how disappointing this is for me," she says. "If you have any other questions I’m open to that."

Full quotes to come...  

David Law

BBC commentator

"Roberta Vinci beating Serena Williams is one of the biggest upsets the sport has seen, perhaps any sport has seen."

Reuters

Jeff Tarango

Former professional tennis player on 5 live sports extra

For the first time ever, the women's final sold out before the men's final because of Serena aiming to win the calendar Grand Slam. It is a shame that Serena is not in it, but also a breath of fresh air that Vinci is there. However, I think a few ticket holders will be disappointed not to be seeing Serena trying to create history.

'Frozen Serena'

Chris Evert on ESPN: "I saw a frozen Serena Williams. I saw a paralysed Serena Williams. She succumbed to the nerves. She is human."

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Top day for Fabio...the other finalist, Flavia Pennetta, is his girlfriend.

Get involved

It's Van Gool: We all love a great champion like Serena but sometimes it's great to see a true underdog triumph.

Dennis Ethan: That's why I love tennis. Every point counts! Congrats Vinci!

EPA

Forza Italia

And quite incredibly, that means we will have an all-Italian women's singles final. Between Flavia Pennetta, the world number 26, and Roberta Vinci, the world number 43.

Unbelievable...

Jeff Tarango

Former professional tennis player on 5 live sports extra

 "You can look back on this in 10 years - and say this is one of the biggest upsets in sporting history, especially with Serena going for the calendar Grand Slam. I can't recall seeing, in the history of women's tennis, the first and second seeds losing in the semi-finals of a Grand Slam."  

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Roberta Vinci is absolutely brilliant. Mad as a box of frogs, but brilliant. Get this woman on the late-night chat shows. Heck, get her her own chat show!

Player reaction

Roberta Vinci: "I'm sorry for the American people, for Serena, the Grand Slam, everything...but today is my day.

"I'm proud of myself, my fight and my game. I'd like to say thank you to my coach and my team - grazie!

"I will enjoy this moment today - and then tomorrow we will see."

AP

Player reaction

Roberta Vinci:  "When I woke up this morning I said to myself I have a semi-final, just enjoy it, don't think about Serena. I didn't expect to win - but I won!

"I said in my mind 'put the ball on the court and run. And don't think about Serena on the other side of the court'."

Player reaction

Roberta Vinci: "This is an incredible moment for me - amazing. It is like a dream. I'm in the final, I beat Serena...phew.

"So many things are in my mind. It was an incredible match, I lost the first set, and tried to stay in every point. I tried to stay focused and not think about Serena. It is the best moment of my life."

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"What gave you the belief that this moment was possible?" Roberta Vinci is asked.

"No," she replies.

Full quotes (from what I must say is an endearingly bonkers post-match interview) to come...

BBC Radio 5 Live Sports Extra

Vinci has never been to a Grand Slam semi-final before, let alone a Grand Slam final.It was a virtuoso masterclass from the Italian - Serena Williams had no answer. New York is in shock.

David LawBBC Radio 5 live sports extra commentator

Game, set and match

Getty Images

That is utterly extraordinary. I think we may just have seen the greatest sporting upset of the 21st century. Roberta Vinci is in tears.

The Italian served out nervelessly for the biggest win of her career, taking the final point with a magnificent pick up off her toes. The Serena Slam is over.

Serena sends another easy volley into the net. Three match points for Vinci...

AP

Serena gets a gimme second serve on the first point, but swats it into the net. Then Vinci plays a lovely volley to bring up 30-0. She's two points away...

Williams 6-2 4-6 4-5 Vinci*

Serena is looking so tentative out here as the dream of the Grand Slam slips away. A leaden-footed forehand finds the net, and she's 0-15 down. But she's not a champion for nothing - she reaches into the locker and pulls out two aces to take her to 40-15. She cleans up the game with an emphatic smash. Drake Watch: pacing nervously. Vinci has a long changeover to think about serving for the match. Against Serena Williams...

AP

BBC Radio 5 Live Sports Extra

The American crowd can't believe this. There a few rows of people in Vinci's box going absolutely ballistic. But everyone else in this 20,000-plus crowd are about to have the biggest balloon popped.

David LawBBC Radio 5 live sports extra commmentator

*Williams 6-2 4-6 3-5 Vinci

You know what we need right now? 'Wannabe' by the Spice Girls. Thankfully the DJ at Flushing Meadows obliges with a burst of the 90s classic over the PA system. Now, can Vinci hang on to her advantage?

Serena gets to 15-30 with a nerveless high putaway. Vinci has gone too defensive here - she's throwing up too many lobs, and the American smashes another one away to bring up two break points. Serena sends the first one long, she's in control of the second rally - but she steers the ball into the tramlines! 

Another tight backhand goes into the net, and Vinci has game point. And she throws in a double! Unbelievable. Serena, though, has lost all confidence on the length of her groundstrokes - another one sails over the baseline to give Vinci a second opportunity. And she takes it when Serena fires wide! She's one game away...

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Jeff Tarango

Former professional tennis player on 5 live sports extra

Serena's game has no firm structure and she hasn't figured out a plan B - she is just relying on being Serena out there. Serena needed to regroup - I think that was a good time to call the trainer. She needs to play some smart tennis to win.

BBC Radio 5 Live Sports Extra

This is an unbelievable atmosphere inside the Arthur Ashe Stadium. Roberta Vinci doesn't care a fig for history - she wants to create her own history. What a story this is.

David LawBBC Radio 5 live sports extra commentator

AP

Vinci breaks

Oh my word. Serena is unravelling like a cheap Christmas jumper out there - two consecutive double faults allow Vinci to open up 15-30. Drake Watch: looking anxious. Vinci has a double break point on her racquet, but puts a simple volley into the tramlines. How crucial could that be?

Vinci then misses a pass, but now it's Serena's turn to net an easy volley, and it's deuce. Serena sends down an absolute missile, and then, something utterly extraordinary.

Serena looks to have won the next point on two or three occasions, but each time Vinci is there, scrambling furiously, to get the ball back, until finally she seals an incredible point with a volley into the open court. A superb reaction, yelling maniacally and pointing at herself, as if to say to the New York crowd 'Give me some love!' 

Vinci then conjures a break point, and to audible gasps from the crowd, Serena fires long. Could the unthinkable be about to happen?

AP

*Williams 6-2 4-6 3-3 Vinci

It's not exactly pretty to watch Serena when she's like this, almost running on fumes, but you have to admire the way she's drawing on every last drop of emotional energy out there.

She's expending plenty of energy out there, as much from the mouth as from the arms - a loud cry of 'Oh no!' follows a misdirected forehand. Vinci, remaining calm amid the tumult, continues to work Serena cleverly around the court, bringing up 40-15 with an accurate forehand, and sealing the game with a big serve.

AP

Jeff Tarango

Former professional tennis player

I think the humidity has affected Serena's racquet - the strings look a lot looser and spongier. I think she could be in trouble here.That was quite rude from Serena - when she won that 40-15 point Vinci looked at her and Serena waved her fist up in her face. The gloves are off.

Reuters

Williams 6-2 4-6 3-2 Vinci*

Vinci is playing the match of her life out there - she plays another fine point that ends with Serena sending up a lob that she marmalises down the line.

Serena needs to get herself going, which she duly does. An error from Vinci at 15-15 prompts an almighty 'Come on!', which she surpasses when a cross-court backhand kisses the line on the next point. A big serve gives her the hold.

Get involved

John McEnerney: Serena has too much of everything - power, experience - for Vinci, fair play to her for giving Serena a scare but Serena to go through.

AP

*Williams 6-2 4-6 2-2 Vinci

Patrick Mouratoglou is earning his corn in Serena's player's box. He's going through his full repertoire of calming gestures and soothing facial expressions. What a pro.

The tide has suddenly turned back in favour of Vinci though - Serena's being sucked into playing this game at the Italian's slow, staccato pace. A backhand that barely reaches halfway up the net encapsulates Serena's malaise. A return pings off the tape and flops into the tramlines, and Vinci is back level.

Jill Craybas

Former world number 39 on BBC Radio 5 live sports extra

Reuters

Serena double faults a lot but there isn't a technical issue with her serve - she just goes for it. She believes in her serve so much she is comfortable going for that second serve and knows she can follow it up at big moments with an ace.

Vinci breaks

Drake Watch: the rapper was on his feet after that last game. Meanwhile, down on court, Vinci is not giving in - she claws her way to deuce with a lovely cross-court forehand winner. Serena sends a backhand wide, and suddenly it's break point. And would you believe it, she hands it over with a double fault. That was not what the doctor ordered. Unless the doctor is Italian.

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Jill Craybas

Former world number 39 on BBC Radio 5 live sports extra

Serena's focus is much better now - she is in the zone. We saw her do this against Bethanie Mattek-Sands and Madison Keys.

Williams breaks

Ooh, a few nerves from Vinci as she throws in a double fault. A coruscating return winner from Serena takes her to 15-30, and another big return forces Vinci to net. 

Two break points for Serena. She nets a return on the first, but she plays a superb point at 30-40, finishing the deal with an emphatic drive volley. First blood to Serena in the final set. 

AP

Jill Craybas

Former world number 39 on BBC Radio 5 live sports extra

Serena has a reason to be frustrated - Vinci played a smart second set, she used a lot more variety and went to Serena's forehand. Serena didn't handle the situation very well, she didn't adapt and made a couple of errors that she didn't expect herself to make.

Williams 6-2 4-6 1-0 Vinci*

Are we one set from one of the biggest upsets in tennis history? Is the Serena Slam about to be derailed by the world number 45? 

Serena to serve first in the final set, which is usually seen a slight advantage. She nets a simple volley on the first point, but she irons out the gremlins and holds to 15.

Piers Newbery

BBC Sport at Flushing Meadows

AP

The Italian media pack, fresh from the Flavia Pennetta press conference, are not far off rubbing their eyes in disbelief. "You're playing bad," Serena told herself towards the end of that set, before smashing her racquet at the changeover. 

This is not new ground for the world number one, however, as this is the 12th time she has been taken to a final set in her 2015 Grand Slam run. So far, 11-0....

BBC Radio 5 Live Sports Extra

Reuters

That was a great point by Vinci after being so nervous - and Serena's racket is D O N E. Done!

Jeff TarangoFormer US tennis player

Vinci takes second set

Reuters

Williams strikes an early blow, swivelling on a cross-court forehand that beats Vinci. she gets an opportunity on the next point too, but she snatches at the forehand and it finds the net.

Serena then gives the second serve the treatment, swatting it viciously up the line, but her next shot flies over the base line. 30-30.

Vinci has the chance to bring up set point on the next point but she misses the forehand up the line and it's break point. but the Italian battles back, manoeuvring Serena around the court and then firing down an unreturnable serve.

Set point, and she takes it! A superb rally ends with Vinci pinning Serena in the corner and the American firing long. What an outstanding set of strategic tennis from Vinci.

Williams 6-2 4-5 Vinci*

Serena is really battling out there - yelling her approval or displeasure after practically every ball. She seals a comfortable hold to 15 with a big roundhouse forehand. Now, can Roberta Vinci close out the set?

Live coverage

BBC Radio 5 Live Sports Extra

Radio 5 live sports extra are up and running with their commentary of today's action - listen to it in the Live Coverage tab.

Reuters

*Williams 6-2 3-5 Vinci

This is very, very canny tennis from Roberta Vinci - she's making Serena play chess when she wants to do kick-boxing. However, amid the well-constructed points from Vinci, the American is starting to land a few blows, and she brings up a break point with a big forehand.

However, Vinci gets herself out of trouble with a gutsy drop shot, before a wayward return and a wild forehand from Serena give the Italian the game. She's one away from the second set...

Williams 6-2 3-4 Vinci*

No problems for Serena in this service game - she whizzes through a blink-and-you-miss-it hold. Now to attack the Vinci serve...

Reuters

*Williams 6-2 2-4 Vinci

Drake's in the crowd today. You know, Drake, the Canadian singer, songwriter, rapper and actor? No? Oh, I give up. Anyway, he's been 'linked' to Serena Williams in the society pages of late, I hear.

His presence isn't doing Serena much good at the moment though - Vinci is more than holding her own with some solid tennis, while the American has really gone off the boil. She nets to allow Vinci to hold to 15.

AP

Pressure on Serena

Piers Newbery

BBC Sport at Flushing Meadows

"Vinci is now getting sympathetic support from the crowd on Ashe, which is largely here to witness Williams take another step towards greatness, but wouldn't mind seeing her pushed. The stats are inching in the Italian's favour in this second set, crucially the one that says she is now winning 60% of points on the Williams second serve. That just puts the pressure on Williams to make her first. Holding serve will remain a battle for Vinci all afternoon, however."

Vinci breaks

Perhaps I was a little unfair on Vinci - she's still showing moments of real skill out here, not least at net, where, like compatriot Pennetta, her skills have been honed on the doubles court.

A lovely volley helps her to 0-30, and then a smoking return brings up three break points. Vinci watches two thunderbolts speed past her, followed by anguished cries from Williams, but she gets a look at a second serve and a good return forces Serena to go wide. What a superb game from the Italian - now can she consolidate?

*Williams 6-2 2-2 Vinci

Vinci is essentially relying on donations from Serena: the American is controlling the rallies and it's all about whether she hits or misses with her bludgeoning groundstrokes. The radar is awry in this game, for the most part, allowing Vinci to hold to 30.

EPA

Williams 6-2 2-1 Vinci*

It's oh-so-simple for Serena out there, the serve really clicking into gear now. Aces number seven and eight close out a simple love hold for the American.

*Williams 6-2 1-1 Vinci

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Here's one for you: Roberta Vinci is the first woman with a single-handed backhand to make the semi-finals at the US Open since Justine Henin eight years ago. Henin was a player who used to give Serena a real test, but Vinci isn't quite in the same class, and from 40-15, she can't close the deal, allowing Serena to get back to deuce. But two tight shots from the American allow Vinci to hold her serve for the first time in four service games.

Get involved

Williams 6-2 1-0 Vinci*

Well well. A slightly off-script beginning to the second set for Serena. She misses a simple volley, and then double faults to give Vinci 0-30. The Italian lies in wait for a second serve, and pounces with a return winner to bring up an unlikely three break points.

Vinci surrenders the first two, but she looks to have taken the third with a winner up the line - before Serena fizzes a quite brilliant, and demoralising, passing shot right onto the line. That's the last sniff that Vinci gets - Serena holds.

EPA

Child's play for Djoko

Williams takes first set

Serena's mum Oracene is sitting in the stands as usual - there's a woman who has seen a fair bit of tennis in her time. She'll be familiar with the crushing return winner that Serena sends past Vinci, as she will with the primal roar of approval that follows. 

Vinci's serve is beginning to look increasingly vulnerable out there, a blowdart at a gunfight, and she sees another winner dispatched back past her to bring up two set points. The Italian fends them off, but Serena wrests a third opportunity, and she takes it when Vinci floats a backhand long. Business as usual on Arthur Ashe Court.

EPA

Williams 5-2 Vinci*

A gorgeous drop shot from Vinci leaves Serena completely flat-footed, and the American sportingly applauds. It's a rare moment of respite for Vinci though, just her third winner, and Serena is increasingly dictating the terms of this match, stepping into court to crush a swing volley past the Italian. The number one seed is warming up nicely, like a microwave curry, and she steers a lovely half-volley off her toes to stretch her lead in what is beginning to look like a routine first set.

Williams breaks

Ominous signs for Vinci. A disdainful swipe of a forehand return takes Serena to 0-15, and then a missed backhand from the Italian has her in a spot of bother at 15-30. Serena is fractionally wide with an attempted pass, but then Vinci misses with a loopy backhand and must fend off a break point. She can't, and Serena is in charge.

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Russia's Alla Kudryavtseva, who reached the quarter-finals of the women's doubles, has timed her tourist trip badly...

Williams 3-2 Vinci*

Never mind the kitchen sink, Serena is throwing the whole range of domestic appliances at her forehand. Two crushing winners bring up 40-0, and a big serve puts Serena back in front.

Williams breaks

This is a big game for Roberta Vinci - can she put a bit of clear water between herself and the apex predator of the women's game? A tight forehand into the net shows Vinci's nerves, and then Serena pummels a two-hander to bring up break point. 

Another one duly follows, accompanied by a yell of 'Come on!', and Serena is back on serve.

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Vinci breaks

Well, well, well. Vinci has an opportunity to get to 15-30 on the Serena serve, but dumps a straightforward looking forehand pass into the net. But the Italian is not going quietly - she forces Williams to go long with a couple of punchy returns, and suddenly it's deuce.

Serena is looking a little cautious out there, and a couple of game points evaporate as Vinci strikes two winners: one mishit, one pummeled. Serena goes long, and whaddaya know, it's break point.  The Italian's spinny, swervy, slicy game is causing Serena some early strife, and the number one seed goes long to hand Vinci an early break. Might we just have a match on our hands?

*S Williams 1-1 Vinci

Serena is immediately looking to come into the net and stamp her authority on this match, but she puts her approach shot into the net. Vinci uses a lot of slice on her backhand, which can trouble opponents for rhythm, but a couple of ominous groundstrokes from Serena take her to 30-30. Vinci scraps her way out of trouble though, and that is a very important hold for the Italian.

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S Williams 1-0 Vinci*

An emphatic start for Serena, who immediately wangs down an unstoppable ace. A couple of unforced errors on both sides betray a bit of tension, before Serena again finds an ace. Another unreturnable serve, and that is a bruising, business-as-usual start for Serena Williams.

EPA

Here we go...Serena to serve first...

Coach's view

Patrick Mouratoglou, coach of Serena Williams, tells ESPN: "I want everything to be free in her mind. She's playing a tricky player, with a great game but unusual for women, with a  sliced backhand and coming to the net a lot. Serena has to be completely focused and mask her emotion. I want her to use the stress to lift her level."

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The players are knocking up - both ladies in pink, Serena sporting a red, white and blue ribbon on her dress in honour of the anniversary of 9/11.

'She was...incredible'

Piers Newbery

BBC Sport at Flushing Meadows

"'I played against her three weeks ago and the serve was.... incredible,' says Vinci. 'Not much,' is Serena's response when asked how much the rain delay affected her preparations. The pre-match interviews are understandably not usually too revelatory, and the American has looked especially glassy-eyed throughout all six she has conducted so far. A big cheer from the crowd, the headphones are removed, phone switched off and she is ready."

The Vinci code

What do we know of Italy's Roberta Vinci? She's playing in her first Grand Slam semi-final today - she's a canny, guileful operator rather than a power player.

According to her profile on the WTA website, she's a good football player and her lucky charm is a stuffed orange dinosaur. 

So basically, this match boils down to this: the weight of history vs a stuffed orange dinosaur.

Old stagers

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This is the second oldest Grand Slam semi-final in the Open era, pitting 33-year-old Serena against 32-year-old Roberta Vinci.

I'm sure you don't need me to tell you that the oldest semi-final was the 1994 Wimbledon clash between Martina Navratilova (37) and Gigi Fernandez (30).

BBC Sport

Slammin' Serena

Yes, next up it's the utterly brilliant Serena Williams, chasing the Serena Slam, having already won the three previous Majors this year.

Her record in Grand Slams this year? Won 26, lost 0. Her record at the US Open over the last four years? Won 26, lost 0. Her record against Roberta Vinci? Won 4, lost 0.

Good luck with that one, Roberta.

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Forza Italia

So, a good day for Italy so far. It could even be an all-Italian final, with Roberta Vinci playing the next semi-final. There is quite a formidable obstacle in her way though...

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Player reaction

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Here's Flavia Pennetta, speaking to the on-court interviewer: 

"It means everything," she says. "I think I played really well - I didn't know how to handle the pressure. It's amazing to be on a court with a crowd like this, who always support me."

Game, set and match

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Pennetta doesn't want to have to serve for this - she's scenting blood and she knows she can finish this now. Another backhand winner brings up two match points. Halep saves one with a gutsy forehand, but Pennetta takes the second! What a magnificent performance from the Italian. At 33, she is into her first Grand Slam final.

Mamma mia

Piers Newbery

BBC Sport at Flushing Meadows

"'Mamma Mia, Flavia!!!' An actual quote bellowed from the press seats in front of me. Pennetta looks much the sharper and fresher, and well on course to complete the first half of an all-Italian final. That would go down well here, I'm sure."

Pennetta 6-1 5-3 Halep*

Everything is working for Pennetta at the moment - she's causing Halep real problems on her backhand in particular. Halep is melting away here - she surrenders the game to love and has now lost the last 15 points in a row...

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Pennetta breaks

Pennetta is tracking everything down like a venerable police sniffer dog - she latches onto a Halep forehand and belts it back past her. The Romanian, who has slipped back into bad habits again, fires long, and is suddenly facing three break points. Pennetta needs only one - nailing a forehand down the line. She's two holds of serve away from the final...

Pennetta 6-1 3-3 Halep*

Pennetta isn't the type of player who is going to pummel every ball, but she is very adept at building through a point and picking her moment to unleash the power. Some hefty winners take her to 40-0, and she seals the deal with a lovely backhand-forehand one-two punch. Level pegging.

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Pennetta breaks

Pennetta's not going to lie down though - she absolutely hammers a forehand into the corner to bring the New York crowd to their feet. Both women are hitting the ball with real venom and precision now, and the winners are flowing. An over-the-shoulder putaway volley, a shot honed on the doubles court, gets Pennetta to 15-30, and then she forces Halep to go long - two break points for the Italian. A double-fault follows, and Pennetta is back on track in what is turning into a real topsy-turvy scrap of a second set.

Halep breaks

For the first time in this match, it's Pennetta with a few questions to answer - how can she respond? Suddenly, Halep is more pumped up than an over-inflated lilo, and she takes the first point with a searching backhand into the corner. Pennetta responds well, taking the next two points, but a lucky net cord for Halep drags her back to 30-30. 

Halep drills a forehand down the line to get to deuce, and just like that, Pennetta sends two groundstrokes long. Halep in charge in this second set.

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*Pennetta 6-1 1-2 Halep

We haven't seen much of Halep's trademark feistiness so far, but there's a glimpse as she nails a forehand and celebrates with a wild double first-pump. Suddenly the Romanian has a bit of momentum behind her, and she finds the corner with another forehand. She nails a backhand down the line, and for the first time, she has a lead on the scoreboard.

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Halep breaks

Halep can only hope that the occasion gets to Pennetta - who has never been in a Grand Slam final - and it just looks like it might. A wayward forehand coughs up 0-30, and just when it looks like Pennetta has got herself back on track, she misses the easiest of volleys and all of a sudden, Halep has three break points. Pennetta fires long, and Halep, without really doing anything, is back in this match.

Pennetta breaks

Halep headed off court during the changeover there - she needs to find a way to reverse the momentum here. But it's not getting any better - Pennetta is battering her with deep groundstrokes, and she sets up an easy putaway that opens up 0-30. 

Halep is struggling to control her power - another backhand flies long and Pennetta has two break points. Halep nets, and her aspirations of making the final are heading south faster than a flock of gulls in the winter.

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'Disbelief all round'

Piers Newbery

BBC Sport at Flushing Meadows

"The media seats are not surprisingly dominated by Italians, always one of the larger press packs on the tennis tour, and they are living every moment of this. One wayward Pennetta volley prompted a magnificent cartoon slap of the forehead from a compatriot, while fists were clenched and knees squeezed as she took the set. A collective discussion is under way in the changeover, disbelief and smiles all round."

Pennetta takes the first set

Legendary Romanian gymnast Nadia Comaneci is in the stands to support her compatriot Simona Halep. Perfect 10? I'll give her a 3 so far, and that's being generous. The second seed is wobbling like a novice on the balance beam, and she surrenders the first set in double-quick time when Pennetta nails a backhand down the line. What a first set from the Italian...

EPA

Pennetta breaks

Halep is showing all the patience of a kid at Christmas here - she's trying to unwrap the big forehand at every opportunity, and more often than not it's ending up in the net. A couple of poor misses give Pennetta two more break points.

On the first point, the Italian does everything right, opening up the court, but then nets a rather too casual over-the-shoulder volley. Pennetta fires wide to pass up the second opportunity too. She's not letting Halep out of jail though - shot of the day, absolutely belting a forehand into the corner, flatter than a pair of slacks that have just been through the trouser press. Break point number three - and this time Pennetta takes it by forcing a forehand error. The Italian will serve for the first set...

Pennetta 4-1 Halep*

Pennetta is moving really well, chasing everything down at the back of the court and hitting crisply off both wings, She's growing in confidence, and Halep's frustration is mounting - a few wild groundstrokes help Pennetta to a straightforward hold.

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Pennetta breaks

Halep is giving the forehand plenty of welly today, but she shows a silky touch too, dinking a delicate drop volley off her toes to fox Pennetta. More shenanigans at net, and this time Pennetta comes out on top, reacting well to punch a volley past the Romanian. 

Halep puts a little too much mustard on another forehand, and suddenly out of nowhere, it's two break points for Pennetta. She manoeuvres Halep around the court superbly, but then sends a creaky backhand into the tape with the court gaping. On the next point though, it's Halep's turn to net, and Pennetta, who has more breaks of serve in this tournament than anyone else, has another one.

Empty seats

Piers Newbery

BBC Sport at Flushing Meadows

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"It's dry, bright, 21C and with a cool breeze in Arthur Ashe Stadium - unusually kind conditions for tennis after the recent extremes of lung-scorching heat and biblical storms. There are probably 4,000 spectators in place, which is not bad for a Friday morning but it does leave 20,000 blue plastic seats on show. It's a marathon not a sprint today though."   

Pennetta 2-1 Halep*

Pennetta is playing in only her second Grand Slam semi-final, and she shows the first sign of a few jangly nerves with a double fault. That allows Halep to claw her way to deuce. A tight backhand from the Italian finds the tape, but she manages to save the break point when Halep sends a gimme backhand wide. 

A long forehand from Halep and a big serve from Pennetta, and just like that the door is slammed on the Romanian.

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*Pennetta 1-1 Halep

With neither woman blessed with a howitzer serve, we could see a few long rallies in this match. Halep is the slightly more mobile player and that serves her well in this game as she chases down a Pennetta smash and the Italian nets. Hold to love.

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Pennetta 1-0 Halep*

Halep begins the contest with a bludgeoning forehand winner into the corner. A couple of cagey rallies as both women feel their way into the contest, before Pennetta returns the favour with an emphatic forehand down the line. Another lengthy rally is ended cleverly by Pennetta when she reels Halep in with a drop shot and then sends a backhand into the open court, and that seals a nerve-steadying hold...

AP

Here we go...Pennetta to serve first...

Halep's hard-court high

Looking for any more pointers on this first women's semi? Well, here's a better omen for Halep fans - she has 37 hard-court matches this year, more than anyone else on the WTA Tour. She's sporting a pink ensemble today, Pennetta in a blue and white dress...

The players are knocking up out there - Halep, who is carrying some rather heavy-duty strapping on her left thigh, has won the toss and elected to receive serve. Mind games...

BBC Sport

Can Pennetta go one better?

Standing in her way is Italy's 26th seed Flavia Pennetta, who loves New York more than Frank Sinatra - she's made the last eight in Flushing Meadows in six of her last seven appearances.

If she can make it here, she'll make it anywhere, right? Well, not exactly - she's only ever made one quarter-final at the other Slams.

Anyway, she starts today's match as a definite underdog, but if you think a Halep victory is assured, consider this - Pennetta leads their head-to-head 3-1. And then consider this...

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Halep on hot form

Simona Halep is bidding to reach her second Grand Slam final - you may remember her taking Maria Sharapova to three sets in last year's French Open.

The diminutive Romanian may stand only 5' 6", but she packs a mighty punch, as Victoria Azarenka found out in their pulsating quarter-final.

If she can make it through today, the Serena Slam might not be such a foregone conclusion as it seems...

Reuters

Hello

Welcome to live coverage of semi-finals day at the US Open. Over the next few hours, we've got Serena Williams v Roberta Vinci, Novak Djokovic v Marin Cilic, and Roger Federer v Stan Wawrinka.

But first up, it's women's second seed Simona Halep of Romania against Italy's Flavia Pennetta.

Supersized semi-finals

America. The land where everything is bigger, and better.

The cars. The hot-dogs. The skyscrapers. The ridiculously protracted presidential contests.

And now, you can add to that list the tennis. Because this is a special king-size, jumbo, footlong semi-finals day.

Not only have we got Novak Djokovic and Roger Federer in action in the men's semis, we've also got the women's semis held over from yesterday - and that means a side order of Serena, and an extra helping of Halep.

Still hungry? Then let's get started...

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