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

I think these love games are a bonus for Ben Shelton.

It allows him to just ease through his games and then he should have the energy to maybe have a crack at Jannik Sinner's serve.

He isn't missing much, is he? He is mixing the play up and really unsettling Sinner at this stage.

Now then, is this a half chance for Ben Shelton? Jannik Sinner gives the American a nice opening of 0-30 as he fires wide.

Shelton can't deal with the pace of Sinner's forehand on the next point, pushing it into the net.

But here we go... Shelton has two break points as Sinner finds the fence.

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

The way that Ben Shelton played the first two points of this match made us talk about him wanting to play high-octane tennis. He has been playing like this from the outset.

If he keeps playing like this and taking it to Jannik Sinner, he is giving himself the best chance.

Ben Shelton doesn't want to be outdone on the serve and he steps it up a gear.

A big serve sets him on his way before Jannik Sinner sends a backhand into the net. And there's another huge first serve straight at the defending champion, who can't adjust quickly enough.

On we go...

Woah. Where has that come from?

Jannik Sinner hadn't served an ace yet, but all of a sudden he slams down three massive ones - one at 126mph and two at 123mph.

Ben Shelton had no chance of stopping those and now the pressure is back on him to stay in this opening set.

Image source, Reuters

Ben Shelton is known for his big serve, but it doesn't seem to be causing Jannik Sinner too much trouble as things stand.

Only one ace so far from the American, who opens up a 40-15 lead by getting low to absorb Sinner's forehand with a a superb drop volley.

And there's the hold as Sinner can't quite get enough on that first serve.

Ben Shelton makes that easier for Jannik Sinner than it should have been, with a series of unforced errors helping the defending champion to a relatively straightforward hold.

Pat Cash
Former Wimbledon champion on BBC 5 Sports Extra and BBC Sounds

Wow. The variety that Ben Shelton is throwing at Jannik Sinner is quite impressive.

That was probably the rally of the tournament. I haven't seen any other guy covering the court like that, skimming and slicing backhands over the net that low, and finishing up with a drop-shot.

It was masterful - but can Shelton keep it up?

Image source, Getty Images

Jannik Sinner flings a backhand wide and Ben Shelton survives by lashing home a volley at the net.

Shelton's dad and coach, Bryan Shelton, loved that and he sends a couple of aggressive fist pumps in the direction of his son.

Wow! After a rubbish drop shot attempt on the previous point, Ben Shelton pulls it out again and this time it works marvellously - sending Jannik Sinner to the floor.

Deuce.

Image source, Reuters

Powerful stuff from Ben Shelton, whose big serve sets him up well to slam a volleyed winner away as Jannik Sinner tries to get back in position.

But the American is undone by a failed drop shot on the next point and its another break point for Sinner.

Jannik Sinner holds up a hand in apology as a net cord works in his favour during a lengthy rally, which he ends with a forehand into a largely empty court as Shelton finds himself pushed wide.

And now the Italian has a chance to edge even further ahead.

It was all going so well for Ben Shelton in this service game, but Jannik Sinner ramps up the pressure with a fine backhand winner before forcing the young American into a miss. Deuce.

Jannik Sinner manages to squeeze a pass around Ben Shelton, but there's too much pace on it and the ball goes long.

After struggling to reach a fiery cross-court forehand from Sinner, Shelton entertains with some brilliant play at the net before swatting away a winner. And then an ace - his first of the match. 40-15.

Lovely from Jannik Sinner, who seems to have found his rhythm now.

The top seed wrong-foots his opponent, firing down a cross-court backhand as Ben Shelton retreats the other way.

Shelton looks like he might be able to force deuce with some great defence work, but eventually he falters with a long forehand.

Image source, Reuters

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

Just keep an eye on the growing tally of unforced errors from Ben Shelton.

At the same time, it is sending a warning signal to Jannik Sinner that anything that he plays short or without weight is going to be cranked.

Shelton is saying that he is going to red-line the response.

We're back level on Rod Laver Arena.

After doing so well to claim an early break, the unforced errors creep into Ben Shelton's game and he gifts Sinner with a wild forehand hit.

Ben Shelton swaps up the pace by dinking over a drop shot that Jannik Sinner gets to but he can't put it away against the advancing 21st seed.

But Shelton has work to do now. Two misses from the American and Sinner has a break point.

Much, much better from Jannik Sinner.

Ben Shelton is able to return the Italian's serves but Sinner is quick to advance and a couple of quick serve-volley combos help him on his way to a comfortable love hold.

Jannik Sinner makes a move to the net, but he doesn't do enough with the volley and Ben Shelton takes advantage with a cross-court passing winner.

And then a big second serve sees him through. He backs up the break.

Image source, Getty Images