Jannik Sinner offers a long, hard look at his box after going down 0-15.

He responds with a forehand winner and an ace but then Jan-Lennard Struff attacks a second serve with a booming return and swoops into the net to level the game.

With a wild cross-court backhand, the German has set point.

Pat Cash
Former Wimbledon champion on BBC Radio 5 Live

Pegula has had chances to have a couple of breaks, she's just had a few bad drops shots on some big points.

An ace down the T seals another straightforward hold for Jessica Pegula.

Back over to Coco Gauff, who will have new balls to work with in the next game.

Greg Rusedski
Former British number one on BBC Radio 5 Live

Sinner has not put down the hammer yet. All of a sudden, it looks like Sinner is pouncing. He doesn't have that ruthlessness, he needs to lift his level.

Struff just needs to carry on risking it and move forward.

Down advantage, Jannik Sinner once again can't capitalise on a second serve. A forehand error from the Italian completes the hold for Jan-Lennard Struff.

Harry Poole
BBC Sport at Wimbledon

While we could talk all day about Coco Gauff’s ‘problematic’ serving, one part of her game that isn’t lacking is her fighting spirit.

It’s clearly a struggle out there for her today, against a quality opponent. Everyone can see and feel that here.

But despite the errors and the double-faults, she is still battling away and doing what she must to stay alive in this match.

Saved with a first serve down the T which Jannik Sinner can only return long. Jan-Lennard Struff lets out a "come on!".

What a return from Jannik Sinner! Dragged wide and deep behind the baseline, he pings back a low cross-court backhand and Jan-Lennard puts the ball into the net. 30-all.

With a loose forehand, Sinner has a break point.

John McEnroe
Three-time Wimbledon singles champion on BBC Two

Jan-Lennard Struff's first serve percentage has dropped below 60% now. He is giving Jannik Sinner more looks and living a bit dangerously here.

However, Jannik Sinner has missed a few second serve returns too.

That will be very welcome for Coco Gauff!

No stress, no drama, just a very straightforward hold to love.

After the rollercoaster nature of Coco Gauff's recent service games, it's a much calmer affair for Jessica Pegula.

She holds to love and keeps this second set on serve.

Image source, PA Media

Great Britain's Alfie Hewett, speaking on court three after beating Netherlands' Tom Egberink in straight sets: "First round matches never get any easier, but it is a privilege to be on these courts and it is certainly something I don't take for granted each year. There were definitely some nerves in the beginning there, a few too many shanks, but it was good to get through in the end.

"I know what Tom [Egberink] is capable of. He has got a great backhand slice and a big forehand as well, so I knew I had to play it smartly. I just felt like I was playing a little bit too much into that backhand side at times and he was knifing it pretty well towards the end of the second set. I thought I did well to keep my serve in that second set and just keep in it."

On winning the men's wheelchair singles title at Wimbledon in 2024: "It is the best feeling in the world. This is the one tournament where I probably don't have the best sleep, but that's because of excitement and the experiences that I've had here. Wimbledon is really a standout for me. Some of the memories that myself, my team and my family have had here over the years have been a real highlight of my career. Hopefully it is even better this year."

Jan-Lennard Struff attacks Jannik Sinner's second serve and follows his return into the net, but Sinner nails a backhand pass. He cocks his head to watch the ball's trajectory as it kisses the tramline. 15-0.

Struff nicks a point back at 40-0, sneaking into the net to gobble up a sliced backhand, but Sinner secures the hold with an ace.

Tracy Austin
Two-time Grand Slam champion on BBC One

Coco Gauff's second serve has been problematic today. She has served six double faults so far and she is only winning 37% of her second serve points as of now.

It isn't helpful when playing against one of the best returners in the game.

Image source, Getty Images

Image source, Getty Images

Coco Gauff's shoulders slump after another double-fault to hand Jessica Pegula another break point.

She clips the line with a sliced approach shot before finishing the point at the net to save it before a finding a very timely ace.

She then hammers an overhead volley in and lets out a roar. Another big hold for Gauff. They all feel big the way things are going.

Jan-Lennard Struff opens his service game with a double fault and finishes it with an ace down the T. Hold to 15.

Tracy Austin
Two-time Grand Slam champion on BBC One

When you hit to Jessica Pegula, you pretty much know what you're going to receive.

It will be a hard and flat ball because she likes to hit it early, she has great timing and she has improved her movement.

She is one of the greatest competitors alongside Coco Gauff. No matter what the score is, she is engaged in every point. She has that aura and that respect as well.

Ace for advantage and this time, Jannik Sinner comes through to hold with Jan-Lennard Struff sending a second-serve return long.

Fighting back to hold in the last game seems to have fired up Coco Gauff.

Jessica Pegula is up 40-15 but Gauff doesn't give it up and as she charges in to meet a slack drop shot from Pegula, whipping the ball down the line for a winner, she's got a break on her mind.

But fourth seed Pegula, as she has throughout this match, stays calm and pushes through to hold.

Encouragement for Gauff, though.

Image source, Getty Images

Ace for advantage.

Double fault for deuce.