Coco Gauff refuses to let the set go without a fight.

Belinda Bencic's serve pops up nicely for the American and she returns beautifully with a forehand winner.

Andrew Castle
BBC Sport tennis commentator on BBC One

Shintaro Mochizuki is out on his feet but loving life!

I mean look there is no secrets from this point in a match, if he gets a set that will be very unusual but if he wins the match that will be headlines. It will be ridiculous.

Shintaro Mochizuki comes through a tough service game as Jannik Sinner goes into the net, before ramping up the noise on Centre Court by encouraging the crowd.

Mochizuki might be two sets and a break down but he's enjoying his time in the spotlight.

Coco Gauff steps up to mid-court and cushions a backhand winner away to lead 30-15 against the serve.

Gauff loses her footing behind the baseline and sends long.

Jannik Sinner punishes a short second serve with a forehand return but Shintaro Mochizuki responds well.

He forces Sinner into a couple of mistakes to get to game point before Sinner steps up with a big forehand to take the game to deuce.

Todd Woodbridge
Former Wimbledon doubles champion on BBC One

Jannik Sinner is starting to unleash here. He has just hit an 86mph forehand winner. It was right in his hitting zone, it just sort of popped up and said: 'Hit me' to him.

Colin Fleming
Former British tennis player on BBC One

Shintaro Mochizuki has had a tough 20 minutes, hasn't he?

He was playing the first points of that tie-break in front of me and you could almost feel from here that his hand was tightening up. It was the first moment where he thought about where he was and what he could maybe achieve in nicking that second set.

It is a double-whammy being broken so early on. I should think Jannik Sinner can move through the gears now.

Image source, PA Media

Coco Gauff continues to find the net.

Belinda Bencic leads in this match for the first time and will serve for the set.

What a turnaround this has been from the Swiss 11th seed.

Surely it's plain sailing for Jannik Sinner from here.

Just as I type that, he serves a double fault, but it doesn't derail the game as Sinner wraps it up with an ace.

Sinner's still not completely happy out there and is chattering away to his coaching team in between points.

Coco Gauff can't get any joy with her backhand either now. She trails 30-15 on serve after hooking low into the net.

Belinda Bencic hammers away at Gauff and gets her reward when the American's backhand lands in the tramlines.

Coco Gauff steps up to mid-court but her forehand lets her down.

And again.

Great defence from Belinda Bencic targeting that forehand and a big hold.

Todd Woodbridge
Former Wimbledon doubles champion on BBC One

Well these are going to be hard points to win for Shintaro Mochizuki if he doesn't come forward.

In the second set summary, we saw 12 of 15 advances was the average so he is going to have to take more risk. If you lose a couple more no problem, but you aren't going to win from staying on the baseline.

Belinda Bencic gets through the first unscathed.

They engage in a rally and it's Bencic who comes out on top as Gauff gets under the ball and sends long.

Image source, Getty Images

Shintaro Mochizuki gets worked from left to right as Jannik Sinner gets his nose in front in the game.

Sinner then returns right at Mochizuki's feet to bring up break point.

Mochizuki prods his backhand long and that is a devastating start to the third set for the world number 151.

Coco Gauff gets off to a positive start 30-0.

Belinda Bencic gets her feet tangled up on the baseline and returns long.

Two break points for Gauff.

Coco Gauff needs to address this run after losing three games in a row.

The American gets to 40-30 and goes on to hold.

No double faults this time.

Todd Woodbridge
Former Wimbledon doubles champion on BBC One

You have to maintain the level in a tie-break, but Shintaro Mochizuki obviously came off it there.

He gave away a few cheap points and made a few poor decisions. I bet his mind just started spinning as he got close to maybe sneaking that second set.

Image source, PA Media

Seven straight points for Jannik Sinner as he steps into the net for an overhead smash which seals the set.

It's a long way back for Shintaro Mochizuki from here.

Shintato Mochizuki is having a word with himself as he finds the net again, before Jannik Sinner's first serve proves too hot to handle.

A forehand return winner from Sinner then brings up six set points.

Sinner's made this tie-break look easy so far.

Chants of "Let's go Coco, let's go" ring around Court One as the players take on some fluids at the change of ends.

Belinda Bencic is the one that's flowing at the moment, though, and the Swiss opens up a 30-0 lead.

Bencic cracks a lovely forehand winner into the corner after forcing Coco Gauff wide and then goes on to hold to love.

Firing on all cylinders now.