Jack Draper's serve really fires when he needs it, two big serves getting him to 30-30 and then a hold when Karen Khachanov forces deuce.

Khachanov is, er, not in the greatest mood.

Naomi Broady
British player on BBC Radio 5 Sports Extra

Andy Murray is laughing at himself, he's that annoyed. What an opportunity he had.

Andy Murray berates himself as he drifts a backhand slice wide after he had done the difficult job of getting into a rally after a supersonic serve.

Matteo Berrettini drills into the net. Errors all over the shop from the back of the court.

Break point Murray.

Matteo Berrettini flops a forehand into the net to give Andy Murray 30-30.

How are those nerves?

Berrettini whacks down a settling ace. But Murray lures him long on the next point to bring up deuce.

Andy Murray uncorks a 127 mph serve - his fastest of the match so far - at 30-30.

He needed that. Another rip-snorter gets right up in Matteo Berrettini's grill to close out the game. There is helium in his heels as he bounces to his stool for a towel down.

Karen Khacanov gifts JackDraper a break point, then makes a huge mistake in raising his finger to his lips and shushing the New York crowd after he saves it on a long Draper forehand.

They don't take too kindly to it, cheering loudly as Khachanov slaps a backhand into the net, and the Russian then misses an easy volley to hand Draper the initiative.

Matteo Berrettini is a sponsor's dream. His kit has various logos - a German fashion designer, an Austrian energy drink. Big blue-chip, copper-bottomed companies all investing in his 1000-watt power tennis and high-beam charm.

But the Italian is right in a wrestle now though. Murray is a closing-time car-park fighter of a player and will do everything to find a way to unravel the Italian mentally.

On we go...

Every time Karen Khachanov gets in front on the Jack Draper serve, the Brit finds an excellent strike to cancel it out, but he still finds himself at deuce.

Now then. Draper angles a backhand over the tramlines to gift Khachanov an early break point, but a huge ace out wide cancels it out.

Another ace is cancelled out by a double fault, before two excellent backhands help Draper come through a tough hold.

Naomi Broady
British player on BBC Radio 5 Sports Extra

"Keep moving and move him," I heard Ivan Lendl say.

Image source, Getty Images

Andy Murray's serve looks a trim, tauter version of the scattergun thing that was floundering about in the first two sets.

He holds to 15 and flips the spotlight back on Berrettini.

A dose of sanity. A sobering hold of serve from Matteo Berrettini. Is he back on auto-pilot seek-and-destroy mode?

Or are there still some screws loosened by his failure to see this out in three?

In the men's doubles, Andy Murray's brother Jamie is trying to mount a fightback of his own alongside Brazilian partner Bruno Soares.

They lost the first set on a tie-break and are 5-4 up on serve in the second against Hugo Nys and Poland's Jan Zielinski. They've just had set points but were unable to convert.

In the mixed, Neal Skupski and American Desirae Krawczyk lead Chris Eubanks and Alycia Parks 7-6 (7-4) 3-2 on serve in the second set.

Naomi Broady
British player on BBC Radio 5 Sports Extra

It's hard, especially over a five-set match, how do you keep your focus each and every point?

You're bound to throw in a looser game every now and again. It's tough to sustain that mental capability, that ultimate focus, for that length of time.

A twist to the twist.

The mojo and momentum is sloshing around the Arthur Ashe court like alcopop on the deck of Magaluf booze cruise.

Matteo Berrettini breaks to love to level up the fourth set.

It's all square on Grandstand!

A lovely put away from Jack Draper at the net, and he levels this third-round tie up.

Much, much better from the Brit, especially considering he went down a break early on.

A tentative forehand from Khachanov finds the net and it gives Draper a set point, but a wicked body serve from the Russian sends us back to deuce.

Oh, and then Draper rustles up a wicked forehand to outmuscle Khachanov and set up a second set point...

Russell Fuller
Tennis correspondent at Flushing Meadows

Murray is in the ascendency at the moment and he is cashing in.

Well, well, well, are we going to see another spectacular Andy Murray comeback?

Matteo Berrettini looks like he has come home unexpectedly early to find his parents putting on an impromptu kabuki theatre performance.

Utterly confused and a little scared.

Andy Murray by contrast has the wind beneath his wings as Bette Midler put it....

Karen Khachanov starts this big service game with an untimely double fault.

His serve gets him out of another sticky situation at 30-30, but he inds himself at deuce with an uncharacteristic miss on the forehand.