Big serve from Seyboth Wild brings up 3-3.

The Brazilian winds up for a big backhand and slams it into the net. 4-3 to Evans.

Evans comes to the net again and it works this time. Seyboth Wild slaps a backhand into the net: 3-1.

Yet another serve and volley from Evans, but the 20-year-old plays him at his own game. He glides across the front of the net like a Strictly winner and taps a graceful backhand winner over. 3-2, on serve.

Ace down the middle, nice start from Evans. 1-0.

Seyboth Wild then takes a seat at the side of the court as the umpire picks up his phone. Not quite sure what that pause was about but it all looks to be sorted now.

Evans is seemingly undisturbed as he glides a delightful backhand winner down the line. He comes forward on the next point, but fluffs the smash and gives the Brazilian his first point of the tie-break. 2-1.

We're on serve in the first set at Arthur Ashe Stadium. Serena Williams is 5-4 ahead against Kristie Ahn.

Evans sets up what should be a straightforward volley as he comes forward and pushes Seyboth Wild right.

But he can't close it out and pushes the ball wide. The Brazilian struggles to land his winner on the next point, leaving the score at 40-30, before bringing Evans forward with a drop-shot and nudging a winner past the Brit.

Tie-break it is.

Seyboth Wild is making Evans work a bit harder for this third set, but it still seems inevitable that the British number one will seal a straight-sets victory.

The Brazilian takes Evans to 40-30 with a sublime forehand winner that lands on the baseline, before the Brit wraps things up with a forehand winner of his own.

A break in the next match would see Evans through to the second round.

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Dan Evans had an opportunity at 30-30, 5-4 up, to take a match point. He wound up for a huge forehand... and smacked it into the net.

Later, a roar of "Nooooo" rang out after another forehand error. It landed wide to give Seyboth Wild another hold.

Judy Murray
Speaking on BBC Radio 5 Live Sports Extra

My common sense would tell me everything is a bonus for Andy from here but because he has such high expectations of himself he's never coming in here to make up the numbers. Even though it is early days and he's testing himself.

You've got to be measured and sensible. It won't happen quickly. This was a great sign today.

Six-time US Open champion Serena Williams lost both of the first two games against fellow American Kristie Ahn, but Williams has now taken the next three and it's back on serve.

British number one Dan Evans was firmly in control in the first two sets against Brazilian youngster Thiago Seyboth Wild but the world number 113 has come alive in this third set.

Evans has just taken the 20-year-old to deuce on his serve but Seyboth Wild held on, firing bullets at the baseline and closing it out with a forehand winner.

Judy Murray
Speaking on BBC Radio 5 Live Sports Extra

I wondered if some of the flatness may have come from coming out on Arthur Ashe and it's empty.

Having played so many huge matches there and knowing how much he loves the New York crowd, to walk out onto the biggest court in tennis and there's nobody there... I wonder how much that would have affected him.

Judy Murray
Speaking on BBC Radio 5 Live Sports Extra

Somebody will be going to the nearest garage or having ice dropped off.

It's going to be really important that he gets the right recovery after going through that.

He's got a day to get ready for the next one. I imagine quite a light day and lots of physio tomorrow.

Serena Williams is now in action on Arthur Ashe Stadium against fellow American Kristie Ahn.

Third seed Williams, aiming to match Margaret Court's record of 24 Grand Slam titles, has made a bad start as she had her serve broken in the opening game of the match and is currently 2-0 down.

Judy Murray
Speaking on BBC Radio 5 Live Sports Extra

This is all a test. It's testing out his body.

To come through four hours and 38 minutes is a massive positive. How he feels tomorrow and what he can bring the next day remains to be seen.

The tennis is there. It was a little inconsistent today compared to what he would have wanted.

Nishioka is a really tricky opponent. Andy had never played him before so it's not just all about him.

Andrew Neill: I have missed you Andy Murray. I remember being a bit emotional after the 1st round exit at last year's Australian Open (ok I left the office in tears) thinking i'd never see you play again but what an emotional rollercoaster tonight! The desire to win is unbelievable

Judy Murray
Speaking on BBC Radio 5 Live Sports Extra

No one's had the perfect preparation because of the pandemic. Andy's got that warrior spirit: never say die

I was looking at his shirt and he was absolutely wringing. It must be incredibly humid like it always is in New York and you don't have the chance to get used to that when you're based in London.

Andy Murray will play the winner of the match between Canadian 15th seed Felix Auger-Aliassime and Thiago Monteiro of Brazil.

It's another epic.

At the moment, this is the score in the fourth set:

Auger-Aliassime 6-3 6-7 (7-9) 7-6 (8-6) 5-5 Monteiro.

Judy Murray
Speaking on BBC Radio 5 Live Sports Extra

I'm absolutely exhausted. I have not missed those rollercoasters one little bit.

At two sets down he looked subdued and flat which is so unlike him. But you can never write him off.

The minute he started to come out with a few "come ons" and roars, I thought he was getting back into it,

When you think what he's been through and the length of the match I was hoping his body could hold up.