Ben Shelton is known for his big serve, but it doesn't seem to be troubling Jannik Sinner too much as the Italian works his way to a 0-30 lead.

Shelton squashes the immediate danger, getting to deuce, but then he goes wide and hands Sinner a break point opportunity.

Mark Woodforde
17-time Grand Slam doubles champion on BBC Radio 5 Sports Extra and BBC Sounds

Shelton looks a bit more relaxed on that backhand now - allowing that talent and ease and power to take over.

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Jannik Sinner doesn't give Ben Shelton another sniff, wrapping up the hold to get on the board in this second set.

Lovely stuff from Ben Shelton. Jannik Sinner stops in his tracks and thinks the American's lob is going long, but it lands perfectly just inside the baseline.

And then, after being 40-15 down, he works his way to deuce with a huge backhand winner down the line.

After finding himself 0-15 down, Ben Shelton ups the ante and rallies back with some big serving and he manages to get out of trouble.

Advantage, Jannik Sinner. That's one part of the job done for the Italian.

He wraps up the opener with a blistering ace after landing a superb cross-court winner. Ben Shelton stood no chance there.

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

There's so much to admire in the way Sinner's striking the ball.

So pure, struck with such authority and linear and low over the net. Like someone launching a spear into the corners and landing in craters at every corner of the court. He's outmaneuvering Shelton every time.

No mercy from Jannik Sinner.

He defends at the baseline before plotting his attack with a move to the net, and he slams down a winner that Ben Shelton has no chance of getting to.

Shelton gets his revenge when he almost takes the Italian out with a brutal first serve which forces Sinner to duck.

The eighth seed apologises, but Sinner waves it away and takes the loss. He's got the chance to serve out the opener now.

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Jannik Sinner has found his rhythm and he's on a roll.

Four back-to-back winners and he grabs a love hold, making it all look incredibly effortless.

The pressure is back on Ben Shelton to hold serve and stay in this opening set.

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

Shelton desperately needed that game. It was looking like one-way traffic at one point and if he was down 5-1 with Sinner to serve, that was probably the set over you would imagine. He's trying to keep the scoreline as tight as he can.

Not this time, Jannik.

Ben Shelton shakes a clenched fist to his team as he gets through that service game by the skin of his teeth.

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Ben Shelton looked like he pulled up there with an injury, but then he goes and lands a huge ace to save the break point and bring us back to deuce.

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

There suddenly feels like a big energy shift in this match, like the bubble's been popped for Shelton.

Ben Shelton briefly escapes, forcing his way to deuce but Jannik Sinner works himself another break point with a forehand winner.

Ben Shelton is very clearly trying to draw Jannik Sinner away from the baseline, where the Italian feels most comfortable.

But the second seed has been unfazed at the net so far and Shelton can't find a way past.

After holding his own in the first few games, it's falling apart slightly for the American eighth seed, who now must fight off two break points.

"Don't change a thing" are the words from Jannik Sinner's box.

After two tight holds, the defending champion storms through his next service game and he wraps up the love hold with a lovely drop shot and then an ace - his first of the match.

That's the first game of this match that hasn't gone to deuce.

Ben Shelton finally cracks.

Jannik Sinner works him from one side of the court to the other and eventually Shelton runs out of steam and he pushes a tired forehand into the net.

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Ben Shelton is under big pressure here.

Jannik Sinner isn't able to make the most of his third break point, but the American gifts him another when his sneaky drop shot fails to clear the net.

Jannik Sinner finds the net on the first break point and Ben Shelton saves the second by going one way and then the other, sending the ball out of the Italian's reach. Deuce.

What a get that is from Jannik Sinner. Ben Shelton looked like he was lining up a huge cross-court strike, but he changes his mind and goes for a lovely drop shot.

Sinner rushes to get there and he brilliantly wrongfoots the American by finding the back corner of the court, around the net post rather than over the net. Shelton can only smile in disbelief.

But he's not so happy now. Sinner has got himself two break points.

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