Simone Jude: Nervy start by #Monfils. Not that I'm watching while working or anything.

We believe you Simone.

Sixteen minutes gone. Five-nil already. Gael Monfils is hoping he can press the reset button on this match and begin again.

He would have hoped Djokovic may be lacking a bit of match-sharpness after only spending six-and-a-half hours on court in his first five matches.

But there is no rust from the world number one. It is just a brutal mauling so far.

Jeff Tarango
Former professional tennis player on 5 live sports extra

I am not sure it is nerves from Monfils. It just looks pretty languid. There is not tenseness, it is like he can't get the serve to the net. 

Monfils really isn't getting his rhythm going. He isn't sure what shot to hit to penetrate Djokovic's game.

Image source, AP

Nervous? Yep. Inside the fourth game and Gael Monfils has already racked up seven unforced errors.

Once again he faces two break points. He saves the first by belting down an ace, before Djokovic goes long with a forehand from the baseline to take it to deuce.

But it is not long before another Monfils error sees him slam a shot into the net. Advantage Djokovic and then it is a second break of serve courtesy of yet another Monfils double fault.

Ah. This might be a bit one-sided. Djokovic storms through the third game. It is 3-0 on the scoreboard. In only eight minutes.

Image source, EPA

Russell Fuller
BBC tennis correspondent on BBC Radio 5 live sports extra

Monfils wasn't doing that in the first five matches of this tournament. That is a bit of a gift for Djokovic.

It is a hot, humid day at Flushing Meadows with the crowd still streaming into the arena. They witness a first break point of the match for Djokovic and a nervous double fault from Monfils then follows.

Oh dear. Not the start the Frenchman was dreaming of last night.

You get the feeling that Monfils needs to have a good start if he is to have any chance of an upset. Once Djokovic gets rolling and in form, he will be so, so difficult to stop.

A huge forehand from Monfils kisses the line to give him a glimmer of a chance of an opening break at 15-30.

But as quickly as the door opens, the reigning champion slams it shut again, winning the next three points, including storming to the net and hitting a winner that is just in for an early lead.

Russell Fuller
BBC tennis correspondent on BBC Radio 5 live sports extra

If these two met at the start of year I would have been utterly convinced that Djokovic would win but here it is not beyond realms of possibility for Monfils.

Image source, Getty Images

And we are ready. Djokovic to serve first. Let's go.

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As Jeff says, is this the time Gael Monfils makes the big breakthrough in his tennis career? Lightning fast and powerful, 6ft 4in tall and one of the most entertaining players on the circuit.

But the trophy cabinet is not as full as he would like. He has six ATP Tour titles, but never reached a Grand Slam final. This is his second Grand Slam semi-final and this would be the biggest victory of his career if he was to be successful.

Image source, EPA

Jeff Tarango
Former professional tennis player on 5 live sports extra

You don't see as much sliding to the ball, as many trick shots or wild drop shots as you did nine months ago from Monfils.

He is a different person. Maybe he woke up and thought 'I'm 30, everyone says I am so talented and what do I have to show for it?'

Kayley Jay: Would really like Gael to win. Haven't consulted Magic 8 ball for a prediction yet, though.

stevedwhittle: Humidity awful here in Brooklyn, sweating just having a cigarette, I would not want to be playing tennis!

This is the first time Gael Monfils has been in a US Open semi-final, but it is a setting Novak Djokovic knows all too well.

The last time he failed to make it into the last four at Flushing Meadows was in 2006.

Not too helpfully for Monfils, in a televised interview just seconds before walking out on court, he is immediately reminded that he has never beaten Djokovic. Probably not the best thing he could hear right now.

Novak Djokovic has become the first man in the modern era to reach a slam semi-final after three retirements or walkovers.

His nine sets and 84 games completed are the fewest at this stage at any major in the Open era that featured a 128 draw and only best-of-five matches.

"In this stage of the season, considering some physical issues I have had, this was the scenario that I needed and I wished for," he said. "Right now I'm feeling very close to the peak." 

"I never experienced something like this - to have three retirements on the road to the semi-finals.''

Image source, Getty Images

If Gael Monfils is feeling confident before facing the reigning champion, he is certainly hiding it well. The Frenchman, seeded 10th, is going for the approach of completely downplaying his chances of winning.

"Novak's a better player than me, definitely. I think I have no shame to say it," said Monfils.

"His consistency, his game, the way he hit the ball clean. So far it's very hard to remember a match where he wasn't hitting the ball clean, maybe one or two a year. It's amazing.

"The way he handles every tactic that we try to make against him, I think so far he's the best. He's a great champion."

A mind-game masterstroke from Monfils, lulling his opponent in before he causes a massive upset? We will see soon enough.

Image source, Getty Images

David Law
Radio 5 live sports extra commentator

Novak Djokovic has looked fine so far, he's looked like the world number one and we have seen his stick-ability resilience.

Overall I think the rest will have done him good because he came into the tournament depleted. 

We will find out today because Monfils has the fitness, ability and form to beat him.

France's Mary Pierce reached the US Open women's singles final in 2005 and hopes for more French success tonight.

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