Kyle Edmund has got a great poker face. There's not a hint of frustration as another big forehand goes wide, but there's some extra oomph on his next serve.

Ward is struggling to return Edmund's serve, twice sprawling and sending the ball flying out of action.

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Kokkinakis could do with a hold here to start the second set, and could definitely do without the net being on Del Potro's side as a kind roll gives the Argentinian the first point.

Great control from the Aussie to put the next two points away. Wonderful return from Del Potro, right at the feet of Kokkinakis makes it 30-30.

Bang! Delicious, whipped passing shot down the right from Del Potro to set up break point.

Big ace from Kokkinakis to save it. And another to get advantage. And another! Triple aces and the Aussie holds.

Two bad forehands from Alex Ward sees a 40-0 lead cut to 40-30 after a positive service game.

A forehand from Edmund is called wide, he makes the signal but Hawk-eye confirms that it's out, and Ward will hold.

Chris Bevan
BBC Sport at Wimbledon

Fans, flora and coach Jeremy Bates are all watching Britain's Katie Boulter get ready for her big moment against world number 59 Christina McHale. Wildcard Boulter, 20, is making her Wimbledon debut after a two-year struggle with illness and injury, and says getting to play at SW19 is a "lifelong dream".

Her brother James phoned me up last week to ask me to write a story about her - let's hope the world number 235 adds another chapter on court 12 later today.

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Here's how that first set panned out for Alex Ward, the world number 869, as he won the first set 6-4.

Edmund raises his racquet in apology as a bobble off the net goes his way, the ball trickling over, before Ward gets his own back with the exact same shot.

That's a stonker of a forehand from Edmund, though, and he'll get his nose back in front.

That's a gimme from Kokkinakis, belting one long and then a big serve from Del Potro sets up a simple winner.

30-0, make that 40-0 as the Aussie fires long on the return.

So, three set points. Del Potro needs just one as Kokkinakis again sends his return past the baseline.

Down comes a 136mph serve from Alex Ward, and Edmund lashes it long and wide.

Another speedy service hold. This second set will be a case of who will blink first?

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Kokkinakis looks to force Del Potro to at least serve for the set and opens up a 40-15 lead.

Eek, missed out there, smashing into the net with Del Potro stranded. No mistakes with second game point - Del Potro to serve for the set.

Kyle Edmund has never won a set at Wimbledon. He fires through his service game here, a double fault proving to be the only interruption.

Really good tactics on show from Alex Ward. He played aggressively from the off, getting forward and taking advantage of Kyle Edmund's early nerves

Kokkinakis opens up his first chance on the Del Potro serve at 15-30 but the 29th seed scrambles well to set up game point.

The Aussie takes it back to deuce, though. A big second serve sees Kokkinakis do little but sky it upwards for Del Potro to put away before the 21-year-old returns long and JMDP is a game away from the first set.

Jonathan Jurejko
BBC Sport at Wimbledon

Alex Ward looks like he is wearing an electronic tag, issued by the law of the land for some misdemeanour, on his right ankle. He's not.

It is extra support for the ankle in which he tore ligaments in an injury-plagued year.

Certainly it isn't bothering him, nor is his previously-dodgy wrist. His movement and hitting has been squeaky clean.

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Nicely done; Alex Ward brings up set point with an ace and consolidates it as Edmund thrashes a forehand long.

Mum has a big smile on her face up in the stands as Ward, a hint of grin on his own face, does a fist-pump in mini-celebration.

Down comes the serve from Alex Ward and Edmund moves forward, but it hits the top of the racquet and pops up out of play.

That's a poor second serve from Ward, sitting up nicey, and Edmund gives it the full hammer blow.

We're at deuce, though, as Edmund overworks a winner...

Ti kanis Kokkinakis?*

Well he's feeling better now after another impressive hold under pressure from Del Potro.

Can he get into the Del Potro serve now?

*(Translation: how are you, Kokkinakis?)

Chris Bradnam
BBC Sport commentator

Kyle Edmund is the overwhelming favourite but when he came out on court he didn't look like he was ranked 50 in the world and his opponent in the 800s.

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Ward is going after Edmund's first serve but he can't do much about that one, plenty of fizz on the ball and Ward darts it into the net.

That's a hold for Edmund, but Alex Ward will be serving for the first set.

John Inverdale
BBC Sport commentator

Thanasi Kokkinakis was born in Adelaide but both his parents are Greek and he's a fluent Greek speaker.

We once asked him who he supports if Greece ever play Australia in any sport and he said he wasn't sure, paused, then went for Australia. I'm sure the Aussie tennis federation would've been unhappy if he'd said Greece.

If his body allows him, he could be a real force.

A shake of the head from Kyle Edmund as he picks up a low backhand and slices it into the net.

Alex Ward's mum Susan applauds as he sends down a good serve that Edmund skews into the net, before tapping a return long. Watching your son play at Wimbledon - it's not a bad birthday present!

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