Jeff Tarango
Former American tennis player on BBC Radio 5 Sports Extra

If I am Daniil Medvedev I would extend the rallies and scrape out an extra ball – and be ready for the approach shot because you know Novak Djokovic is trying to shorten the points.

It feels a much more even contest now.

Medvedev has relaxed into the final, while there are some signs that Djokovic is perhaps beginning to feel some stress. He'll have to serve to stay in the set.

Image source, Getty Images

Djokovic has an exchange with his team as a series of unforced errors allow Medvedev to capture a comfortable love hold.

Now the scoreboard pressure really is on Djokovic, who had to come through a marathon game when last serving.

David Law
Commentator on BBC Radio 5 Sports Extra

Novak Djokovic is playing Plan B tennis right now, and it is off the charts.

Jonathan Jurejko
BBC Sport at Flushing Meadows

After one hour and 44 minutes, Daniil Medvedev earns his first break point of the match.

Whatever is going on with Djokovic physically has surely provided the Russian with a confidence boost that this guy is fallible.

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Incredible. Djokovic calls for more from the crowd after ending a brilliant point with an angled volley to save the break point.

A gutsy drop shot then catches Medvedev out for game point and there are to be no more opportunities here.

The crowd cheer as Djokovic punches the air to celebrate a massive hold of serve. He was clearly struggling in that game, but Medvedev just could not take advantage.

Djokovic is primed at the net but only needs to watch as Medvedev rolls a forehand into the net.

It's Djokovic's turn to falter next, though, setting up a third deuce.

And Medvedev will have his first break point of the contest!

Frustration for Medvedev, who wastes a chance to attack a second serve with a disappointing miss.

Double fault! Djokovic is suffering a bit of a dip here. You sense Medvedev has to make a move right now.

Medvedev reads a drop shot, racing forward and whipping a punishing forehand deep into the court to reach deuce.

A grimace from Djokovic. A first opportunity for Medvedev.

Medvedev probably wants to try and keep grinding Djokovic down as much as possible after seeing his opponent lying down and breathing heavily in that previous game.

The Russian is struggling to gain a foothold in Djokovic's service games, but a double fault may offer him a way in at 40-30...

Russell Fuller
Tennis correspondent on BBC Radio 5 Sports Extra

We have seen this from Djokovic before though. He likes to let the crowd know he is struggling physically and he enjoyed those few seconds on the ground.

A bit of showmanship but we’ve seen him come back from these before.

Back over to Novak Djokovic, with a clean record on serve in set two.

He extends his run of service points to 13 with a volley, but his streak ends there with a weak forehand finding the net.

Jonathan Jurejko
BBC Sport at Flushing Meadows

Either Djokovic isn't feeling great or he's giving Matthew McConaughey - who is sat in the Serb's box - a run for his acting skills.

Djokovic theatrically tumbles to the floor after a 31-shot rally doesn't go his way.

I mean, I'd be dizzy after a two-shot rally against Medvedev - presuming I'd once be able to get a ball back - so it's difficult to judge.

At the changeover Djokovic asks for a bag of ice.

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Djokovic seems to be fine as he guides in a backhand winner for deuce, but Medvedev eventually gets himself over the line with an ace to close another exhausting game.

Medvedev raises his racquet above his head in celebration. That's a huge hold.

We wait to see exactly what is going on with Djokovic. That was all a bit bizarre.

Annabel Croft
Former British number one on BBC Radio 5 Sports Extra

There was nothing left in the tank for any more tennis. Novak Djokovic is absolutely spent at the moment.

It almost seems he has low blood sugar where he goes a bit dizzy.

Jeff Tarango
Former American tennis player on BBC Radio 5 Sports Extra

Never seen anything like it.

The number one player in the world completely exhausted.

Oh, that's an odd one! Djokovic almost takes a tumble as he steps into a backhand, dropping his racquet as the ball drops into the net.

Medvedev is unable to complete the job but he'll have another chance after Djokovic nets - and then hits the floor.

Hmm. Not sure what that one was about either. He just throws himself to the ground after a long rally.

Jonathan Jurejko
BBC Sport at Flushing Meadows

Oh, stop it!

Novak Djokovic has showed all facets of his greatness this evening, throwing in a delectable drop-shot to further illustrate his confidence.

The touch is so exquisite that a decent number of fans climb to their feet and applaud in admiration.

And here comes Djokovic.

The Serb reaches a first break point in this set as Medvedev falters.

But he rescues the situation efficiently with a volley.

With Djokovic so far untouchable on serve, it feels a case of how long can Medvedev hold out for.

A couple of morale-boosting forehands put him on course for a relatively comfortable hold, but Djokovic comes back. Deuce.