Whatever tonic was whisked up for Novak Djokovic as he left the court initially looks to have done the trick as he goes 40 love up, but Holger Rune battles back.

At 40-30, though, Rune overhits one to hand his opponent the game.

Emily Salley
BBC Sport at Wimbledon

Novak Djokovic races off the court at the change over.

But he's back just as the umpire calls "time". No sign of a medical time-out.

Image source, Getty Images

Barbora Krejcikova speaking on court after beating Danielle Collins to reach the quarter-finals at Wimbledon for the first time:

"It's a great feeling. It's a huge honour to be here and to play on Court One at Wimbledon. It's just unbelievable and I'm really honoured that I'm here and can play in front of a crowd that is cheering. It's a gift."

On being able to call on her experience:

"It's an advantage that I've played here a few times. Not so much in singles but doubles a few times. It's a magic place and it's a dream to be here."

On facing Latvian 13th seed Jelena Ostapenko in the quarter-finals:

"I'm looking forward to that much but I'm just going to enjoy the victory today. It's the first time I'm in the quarter-finals, so we'll celebrate tonight and have some good food. I'm going to prepare the best way so I can get one step further."

Pat Cash
Former Wimbledon champion on BBC TV

You’ve got to be concerned if Djokovic is rubbing his stomach. You’ve got to remember he’s coming in with very little tennis and he’s had the operation.

That messes you up having surgery, the anaesthetic and everything else. It’s certainly not going to make him any stronger.

Holger Rune takes a game to love for the first time in the match to take the lead in the second set. All gone with serve thus far.

At the conclusion of the fifth game Novak Djokovic jogs down to the locker room for some attention

Emily Salley
BBC Sport at Wimbledon

Yep. There's something not quite right with Novak Djokovic.

The Serb grimaces after racing to reach a Holger Rune return and he keeps putting a hand to his stomach like he's in some serious pain.

Novak Djokovic requested to leave the court quick break, which was turned down by the umpire, apparently. Even being Wimbledon royalty you cannot get your way sometimes.

Holger Rune is slowly creeping into this match but at 40-30 Novak Djokovic serves an ace to keep himself on level terms.

Image source, Getty Images

Emily Salley
BBC Sport at Wimbledon

Novak Djokovic seems to be clutching his stomach in between points.

I wonder if there's a bit of a problem for the seven-time Wimbledon champion.

Barbora Krejcikova begins with an ace.

A double fault from Krejcikova and Danielle Collins has a chance to break - she can't take it but does convert when she gets another opportunity.

It would be a remarkable turnaround if Collins keeps this up.

Laura Robson
Former British number one on BBC Radio 5 Live and BBC Sounds

Much more aggressive from Holger Rune, coming out and going for his shots a bit more. Being passive in the first set was not doing the job.

Holger Rune's best service game so far. Meanwhile, Novak Djokovic is having a bit of whinge at the umpire. What's got the GOAT's goat?

Here's how the Serb closed out the first set.

Pat Cash
Former Wimbledon champion on BBC TV

I think Djokovic is still lightning fast but is a fraction slower coming out of that forehand corner and seeing a lot of players, particularly Alcaraz in last year’s final just serve out there all the time.

Emily Salley
BBC Sport at Wimbledon

Ouch! That's got to hurt.

Holger Rune whips a forehand return, but it fizzes wide and hits one of the ballkids that are kneeling at the bottom of the umpire's chair.

Rune is quick to apologise and check that he's alright.

A fist pump followed by a mop of the brow after a stunning forehand from Holger Rune puts him 30-15 up on Novak Djokovic's serve, but the Serb quickly gathers himself to take the game.

Emily Salley
BBC Sport at Wimbledon

There's the first set done and dusted in less than half an hour for Novak Djokovic.

He said before this match there would be "fireworks", but it's all going to be over rather quickly if he keeps going like this.

A chance for Holger Rune to set the tone for the second set and he does just that. Novak Djokovic with a couple of unforced errors hitting the baseline hands the young Dane the first game.

Fair play to Danielle Collins. With a place in the quarter-finals at stake she is refusing to allow this injury to get the better of her.

Collins holds to 15.

Barbora Krejcikova to serve for the match.