Courtney Nguyen
WTA reporter on BBC Radio 5 live sports extra

Edmund has served 11 aces, and Isner 14, but it's the physicality that's making the difference. Edmund is ambitious, wants this win, doesn't seem scared and has earned this chance.

He's withstood the pressure and executed his points. He seems to have a good head on his shoulders, but Isner is a great competitor and he'll be able to reset himself and will be ready to go the distance. He's done it before!

David Law
Radio 5 live sports extra commentator

This would be a stunning result for British tennis and certainly the biggest of Kyle Edmund's career, if he can pull this off.

Meanwhile two-time champion Rafael Nadal is starting his third-round match against Russian Andrey Kuznetsov over on Arther Ashe Stadium.

Nadal is the favourite against the world number 47, now that he appears to have fully overcome the wrist problem that restricted him earlier this season, but could Kuznetsov cause a shock?

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Courtney Nguyen
WTA reporter on 5 live Sports Extra

John Isner walks off court and shakes his head, wondering what is going on. On the other side of the net he has a youngster who can taste it.

John Isner serves at 30-30, he has to hold or he'll be 2-1 down.

The ball is in play and a rally breaks out, not good news for the tired giant. Kyle Edmund rips one just a foot or two to Isner's left and he doesn't move.

Set point Edmund. Isner rushes to the net and will volley while on the move and it's into the net. He was moving at pace and couldn't get it right. Edmund is one set away from the last-16.

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David Law
Radio 5 live sports extra commentator

Edmund has taken three sachets of salt and poured them into a bottle of water.

John Isner holds serve in around a minute and then jogs to his chair at the pace of a sumo wrestler tackling mile 26 of a marathon.

Novak Djokovic must be sat at home thinking if Isner gets through, he will be able to pull out a chair on the baseline and beat the American in the last-16.

Kyle Edmund holds with ease too. This is now all in Edmund's hands you feel.

After holding his serve to move closer to a second set on the board, Kyle Edmund asks the umpire for sachets of salt. He must be concerned with cramping himself, he's struggled from that in the past.

John Isner's first-serves in has fallen to 18% in this third set.

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David Law
Radio 5 live sports extra commentator

Isner's legs are not working properly.

Cold blooded stuff from Edmund. He is playing the sort of tennis you play when your opponent is struggling physically.

John Isner walks to the back of the court to serve at 40-30, he looks like he's just run the Grand National with Kyle Edmund on his back.

A kick serve takes off when it lands and Kyle Edmund can't get it back. Isner is going to have to rely on that serve more and more if he is as tired as he looks.

He's played 11 sets in this tournament so far. Jelly legged.

David Law
Radio 5 live sports extra commentator

He's starting to cramp Isner. He's having to flex that left hip of his.

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John Isner has run 3,674 feet according to the US Open website. Kyle Edmund 3,490 feet.

Get him running young Kyle, he's clearly not keen on it.

A lovely sliced serve across the service box from Kyle Edmund gets John Isner lunging and he balloons a ball into the stands to give the Briton that game. That's 3-0 in the third.

How can Isner be so tired? They've played 83 minutes.

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A 103mph serve from Isner and Kyle Edmund gets it back, what follows is a pathetic drop shot attempt from the American, it's a hybrid of drop and cross court effort. In a nutshell it's a nothing shot and just screams tiredness.

Can Kyle Edmund pounce, he can, taking advantage of the second serve to break. Isner shapes as if he is going to smash the racquet. Go on, do it, you know you want to. 

He refrains. Chicken.

Isner looking a little tired Daniel. 

David Law
Radio 5 live sports extra commentator

The lengthy rally that Edmund dragged Isner into has taken its toll on Isner. It seems like that last Edmund hold could be a big, big moment.

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Courtney Nguyen
WTA reporter on 5 live Sports Extra

That is an absolutely huge hold. He was outplayed for the first three points.

Kyle Edmund lashes his body so his chest points at the sky, it's a show of anger as he finds the net to trail 40-0 on his serve in the third-set opener.

These are critical times, saving three break points looks a hard task, the momentum is shifting. A rally, Isner goes across court and wide, a fist pump from Edmund and he shouts at himself.

Another rally, a desperate reach sees Isner just land a ball in play, with his next shot he's long and he puts his hands on his knees as the third  break point evaporates into the Big Apple air. Great hustle from Edmund, he earns game point and gets it done.

That's a big hold. He looked done.

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