That is absolutely horrible to see.

Jasmine Paolini thumps down an ace and Madison Keys decides enough is enough. She is in tears as she leaves court.

It's not the way Paolini would want to win the match but she is in the quarter-final of Wimbledon for the first time.

Such a shame as it had been an absolutely brilliant match.

Tim Henman
Former British number one on BBC TV

Ugo Humbert is still maintaining the belief that he can begin to turn things around.

The first two sets were a very unfair reflection, Humbert was playing all the tennis but not getting the rewards.

Now he has to back it up with a strong service game.

Mark: If the injury is as bad as it looks, it's probably best not to play on. Even if she wins, I doubt she'll be able to play on after this

It wouldn't come in the second set but Ugo Humbert breaks first in the third.

He thumps his chest in celebration when Carlos Alcaraz's volley goes long but maintains an expression of steely determination.

Lots of work to do for Humbert but he's still fighting in this match and he deserved that break for his efforts since the start of the second set.

Marion Bartoli
Former Wimbledon champion on BBC Radio 5 Sports Extra and BBC Sounds

It is quite painful to watch to see Keys suffering so much physically.

That whole leg just can’t function anymore.

Image source, EPA

Oh no. Madison Keys is in tears as Jasmine Paolini plays the drop shot and she just can't muster up an attempt to run for the ball.

She does still have power from the baseline and after Paolini brings up two break points she saves the first with a big forehand.

But, she double faults and that's the break for Paolini.

It's a real shame for Keys, though. We've had a heck of a match on Court One and until the injury she looked well on her way to victory.

Two crisp forehand winners, including a fabulous return, get Ugo Humbert to 30-30 and a wayward forehand from Carlos Alcaraz takes it to deuce.

Another crunching forehand from Humbert and he's got a break point...

Tim Henman
Former British number one on BBC TV

Ugo Humbert has nothing to show for getting stuck into Carlos Alcaraz's service games.

He's got to keep believing and keep asking the questions.

Madison Keys is back on court with heavy strapping to the top of her left leg. She is still moving very gingerly.

Jasmine Paolini has been hitting a few balls in the break and she takes the first point off the Keys serve. I can't believe the American is carrying on actually. She is seriously hampered here.

It's Carlos Alcaraz's turn to rue a missed opportunity as he misses with a forehand under no pressure at 0-30.

Ugo Humbert won't mind, though, he takes the gift and serves it out to 30.

The covers are coming off the outside courts and fans are wiping down their seats with whatever they can find.

Let's hope that pesky rain holds off for the rest of the day.

Image source, PA Media

Straightforward hold for Carlos Alcaraz to begin the third set.

There wasn't the relentless pressure from Ugo Humbert we saw in the second, but he had the chance to make that game a little trickier for Alcaraz than it was but plonked a drop shot into the net when anywhere over it would likely have been enough.

Maybe Alcaraz's remarkable ability to reach seemingly lost causes on that set point has got into the Frenchman's head?

Here's how Madison Keys closed out that dramatic second set.

Can she get it done here? It looks like she is going to go off court for the rest of the medical timeout but she is certainly walking somewhat gingerly.

Russell Fuller
Tennis correspondent on BBC Radio 5 Live and BBC Sounds

Keys looks quite a dejected figure as she walks slowly to the chair.

She's at it again.

Jasmine Paolini comes through with a hold to 15 and the pressure is back on Madison Keys. It looks like she was just trying to get to the change of ends and indeed, the physio is out as soon as the American sits down.

It looks like she was holding her groin but who knows.

Image source, Getty Images

Tim Henman
Former British number one on BBC TV

Carlos Alcaraz has phenomenal foot speed, movement and balance.

He asked his opponent to hit one more shot and that last shot proved very, very costly for Ugo Humbert.

Marion Bartoli
Former Wimbledon champion on BBC Radio 5 Sports Extra and BBC Sounds

It has been a very physically intense match for Keys and she did so well to come back into that match.

She has pain in her hamstring and she is limping. What a turnaround.

Well, well, well. It's not over til it's over.

Jasmine Paolini came back from 5-1 down in the last set to take it to a tie-break, surely she's not going to do it again?

She breaks Madison Keys at the second attempt when the American goes wide with her forehand.

Keys looks like she is limping a little. Let's hope that's not too serious.

Srosh Khan
BBC Sport at Wimbledon

Everyone else disappeared as it belted it down with rain earlier.

But, BBC Sport presenter Chetan Pathak has got to be the bravest man here.

He was presenting on the BBC News channel while we got thunder and lightning warnings.

It's not all that glamorous is it?

Image source, BBC Sport

Emily Salley
BBC Sport at Wimbledon

Wow. How on earth did Carlos Alcaraz stay in that point?

The crowd absolutely loved it and so did the Spaniard, who whacks his hands up in the air with his fingers pointed to the sky.

Humbert will be kicking himself after squandering those break points earlier in the set.