Superb defence and even better hitting from Del Potro to move to 30-0.

Ace.

Ace.

Done. Delpo consolidates the break in ruthless fashion.

Billie Jean King
Six-time Wimbledon champion on BBC Radio 5 live

Kerber has had a challenge because when you become number one in the world what happens then is you get the pressure that goes with it. If you don't understand that part, if you don't really embrace it, you will have trouble. I think she has had a challenge with that. I think she was surprised how much more media coverage and requests she gets.

Falconi has to match Kerber's aggression, and she's doing it nicely, darting forward and flicking two big shots beyond the world number one.

That brings up two break points - and Falconi gets the break as Kerber slashes a loose forehand into the net! That was all a bit odd.

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Two backhand errors see Edmund trail, but he levels for 30-30 with an ace on the line, and a hold of serve follows.

He might run away with it from here.

Is Kokkinakis surrendering the initiative here? He complains about an awkward bounce but that matters not - it's 15-30 to Delpo.

Make that 15-40 as the Aussie fires long. Two break points.

Ugh, a double fault and Del Potro breaks back. He looked lost for four games or so but has come roaring back.

John Lloyd
Former GB Davis Cup captain on BBC Two

Ward is walking at the speed I run, very slowly, just trudging along. It's all laboured. Whereas Edmund is skipping away to get ready for the next point.

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At Eastbourne, Kerber looked a bit like her feet were stuck in concrete. Not today.

It's third time lucky for the German as she breaks Falconi again. Falconi had some lovely play in tha match, a dinky little drop shot the highlight, but Kerber can be so aggressive.

Alex Ward knows he can't afford to throw his services games away like he did in the third set, but he goes 0-30 down after a double fault.

And then he nets to hand Edmund three break points.

One is saved after a baseline rally as Edmund nets, and another is saved when Ward finds the corner with a lovely winner.

The break is Edmund's, though, when Ward fails to clear the net with a forehand.

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Mischa Zverev turned over Bernard Tomic in straight sets. Watch his winning moment below.

Despondent Delpo needs to get angry.

Here it comes - clattering those thunderous forehands around the court.

One goes far too long but the follow up is a sublime winner to secure a vital and comfortable hold.

Jonathan Jurejko
BBC Sport at Wimbledon

Alex Ward's mum Sue has been joined in the pass holders section on Court Three by Tim Henman's dad Tony.

You remember him. Neat grey side-parting, calm and composed demeanour. Even when his son was in the midst of a nerve-jangling Wimbledon semi-final. Twenty years ago he looked like Tim would look in his 50s. No way he looks like Tim would look in his 70s.

Proper Wimbledon royalty.

A very easy hold to love from Kokkinakis, finished off with a deft drop shot with Del Potro nowhere.

The Argentinian looks laboured, flustered and increasingly despondent out there.

This third set is racing away from him at the moment.

Alex Ward made it hard for him, but on his third attempt, Kyle Edmund takes the third set in 29 minutes.

Onto the fourth we go...

Thanasi Kokkinakis is firmly on top now, having carried his momentum from the second set into the third.

Here he is breaking Juan Martin del Potro's serve on the way to taking the second set.

Oh! A stunning recover from Kerber - she adjusts at the last second and flicks a backhand, on the move, beyond Falconi.

This is a positive start from Kerber, not having to move around much, and she holds.

Kyle Edmund double faults for 15-15 but edges ahead again with a sturdy ace.

The world number 50 misjudges a winner down the line and it falls the wrong side of the paint. 30-30.

But a sublime backhand brings up set point. Edmund reviews a call on Ward's return, but the decision was right - it fell inside the lines - and we go to deuce.

Ward smacks into the net and Edmund has a second set point...

John Inverdale
BBC Sport commentator

Del Potro looks rattled as he's been called for foot faults by line judges at either end of the court. Maybe he needs to just move his feet half an inch back. They are big feet to move, though.

Oh boy! Kokkinakis is flying now. Three points in a row on the Del Potro serve, including a couple of screaming winners and he sets up three set points.

Delpo saves the first then a second foot fault call as him glaring at the line judge and the line.

Second serve - Kokkikanis gets ahead of himself looking for another big winner and fires wide.

The Argentinian fires his first serve well wide and clatters the second into the net. His second double fault and Kokkinakis breaks. Those foot fault calls seem to have got into Delpo's head.

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