Boris Becker
Three-time Wimbledon champion on BBC TV

Once Novak gets you locked in to a rally he has got you where he wants you. You have to play quick points against him.

Once he has you moving he is very difficult to beat.

Bautista Agut loves playing Novak. He has beaten him twice this year, he has Novak’s number.

He is a very diverse player. He’s not afraid of big names. Novak has to be careful.

Jonathan Jurejko
BBC Sport at Wimbledon

My eyesight isn't the sharpest but I'm pretty sure Federer was hitting with retired Finnish player Jarkko Nieminen, a former world number 13.

Sure we'll find out for sure when their end-of-practice photo is uploaded onto someone's Insta page.

Image source, BBC Sport

Out they come! Novak Djokovic has a glance up to the sky. It's a little cloudy but the sun is there.

Centre Court is full.

Novak Djokovic is bidding for a place in the final for the sixth time. Roberto Bautista Agut has never reached this stage.

The Spaniard, seeded 23rd, has already beaten Djokovic twice this year - in Doha and Miami. Can he make it three times in a row in the biggest match of his career?

It's only the world number one and defending champion, after all.

Image source, BBC Sport

Pat Cash
Former Wimbledon champion on BBC Radio 5 Live

I don’t think its going to be as easy as people think for Djokovic. Bautista Agut is a good player.

Jonathan Jurejko
BBC Sport at Wimbledon

Always being watched...

Roger Federer's coaching team - and the cameras - eye his every move as goes through his paces before #Fedal40.

The Swiss great has been on a practice court in a peaceful part of Aorangi for about 40 minutes, whacking back forehands and backhands in what I'd suggest is a more intense session than usual.

Image source, BBC Sport

John McEnroe
Three-time Wimbledon singles champion on BBC TV

It’s rare to see a guy this big with this type of flexibility, movement and balance.

Djokovic is a human backboard. He gets to everything. He drives his opponents crazy.

It would be a monumental upset – despite Bautista Agut beating him twice.

It's almost men's semi-final time!

Novak Djokovic and Roberto Bautista Agut will be waving to the Centre Court crowd any minute.

Image source, Getty

Britain's Andy Lapthorne speaking on BBC TV: "It means absolutely everything. Well done to David and Koji and thanks everyone for coming. I dreamed of playing here, it's full, and tomorrow we will play on an even bigger court.

"Thanks so much for being here. It means the world to me. It means absolutely everything. This, for me, is the world.

"Thanks to my team that have put up with me, thanks to the All England Club for the wildcard and believing in me and thanks to Dylan for playing alongside me.

"Tomorrow we go up against each other and I hope everyone comes out to support so we can get this sport out there and on TV more often."

Patrick Mouratoglou
Serena Williams' coach on BBC Two

Having these three guys, Nadal, Federer and Djokovic, playing that level at the same time is unbelievable. I can't imagine how many Grand Slams they'd each have if they weren't all playing at the same time.

Dylan Alcott speaking on BBC TV: "First and foremost, congratulations to Koji and David. It means a lot for us to get to Wimbledon. We're professional athletes that train just as hard as the guys playing on Centre Court. You can't tell me people don't want to to watch this - there's a line of people trying to get in.

"To Wimbledon, thanks very much for having us. To Andy, thanks for playing doubles with me - but in the singles tomorrow I hope I pump you.

"Thank you everyone for the support - everyone at home and here please tell your friends. Paralympic sport is amazing and we want to pave the way for the next generation to come."

The Aussies, innovating with Wimbledon celebrations since Pat Cash in 1987...

David Law
BBC Radio 5 Live tennis commentator

David Wagner: "Firstly congrats to Andy and Dylan on a great match. It's really the biggest dream you can have to be included in all four grand slams. It's unreal for us. To play on the grass here is a real treat and a special honour and something that goes well beyond us and goes to the people that got us here. We owe a lot of people thanks and gratitude."

By the way, we are go, go, go on BBC Two.

John McEnroe and Sue Barker are courtside as the crowd's file in ahead of Roberto Bautista Agut and Novak Djokovic's semi-final.

Tune in at the top of this page.

Nick Mullins
BBC Sport commentator at Wimbledon

That is a thrill that will live with them for the rest of their lives.

Sugeno and Wagner pushed them so hard in the second set, but the will of Lapthorne and Alcott took them over the line.

We are into a second-set tie-break over on Court 14 as Andy Lapthorne and Dylan Alcott attempt to close out a historic quad wheelchair doubles title win...

Watch over here.