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Huge congratulations to Alfie Hewett! Onwards and upwards for the final!
Rachel, London
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LIVE: Novak Djokovic 4-6 Jannik Sinner in second semi-final
Britain's Arthur Fery beaten in straight sets by second seed Alexander Zverev
GB's Alfie Hewett beats Gustavo Fernandez 6-7 (2-7) 6-0 6-3 to reach fifth successive Wimbledon wheelchair singles final
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Elizabeth Botcherby, Emma Smith, Phil Cartwright, Marissa Thomas and Nicola Pearson
Huge congratulations to Alfie Hewett! Onwards and upwards for the final!
Rachel, London
*Sinner 6-4 0-1 Djokovic
Harry Poole
BBC Sport at Wimbledon
Jannik Sinner was hitting big and clean during his hitting session earlier this afternoon. He has certainly carried that into this match - and some.
The world number one hit twice as many winners as Novak Djokovic in that first set, while making fewer unforced errors, in what was a statement 40-minute opener.
You can't help but wonder just how much Djokovic is still suffering from his marathon quarter-final, but you sense he needs to gain a foothold very quickly in this match given how his opponent has started.
Djokovic clenches his fist as he holds in the opening game of the second set.
Fernandez 7-6 (7-2) 0-6 3-6 Hewett
Image source, PA MediaAlfie Hewett shakes off the disappointment of the last game and moves to 0-40 on the Gustavo Fernandez serve - three more match points.
The first is wasted as Hewett goes long... but then Fernandez goes long himself and Court One roars!
Hewett spreads his arms wide in delight, he has won many matches at Wimbledon but he had to work particularly hard for this one.
The British second seed is into a sixth singles final at the Championships. He will face Japanese world number one Tokito Oda, who beat Hewett in the final last year.
Sinner 6-4 0-0 Djokovic*
Eugenie Bouchard
Former Canadian tennis player on BBC One
Jannik Sinner looks very engaged, he was giving intense positive looks to his camp.
Novak Djokovic was speaking quite angrily to his box so he was not pleased with how that set went down.
Sinner 6-4 0-0 Djokovic*
A reminder that the winner of this semi-final will play second seed Alexander Zverev in Sunday's final.
Zverev beat British wildcard Arthur Fery in straight sets earlier today.
Sinner 6-4 0-0 Djokovic*
Andre Agassi
Former Wimbledon champion on BBC One
Jannik Sinner has established that he is going to take away any second serves that Novak Djokovic has.
It seems like Sinner is ready for it all.
*Fernandez 7-6 (7-2) 0-6 3-5 Hewett
Gustavo Fernandez with a lovely forehand, and he breaks Alfie Hewett who was serving for the match.
On we go...
Sinner 6-4 0-0 Djokovic*
Image source, Getty ImagesThe world number one leads on Centre Court.
Fernandez 7-6 (7-2) 0-6 2-5 (40-40) Hewett*
A beautiful backhand brings up match point for Alfie Hewitt. He puckers his lips in a way that shows he really, really enjoyed that shot.
But a cross-court forehand from Gustavo Fernandez takes us to deuce...
*Sinner 5-4 Djokovic
Novak Djokovic saves the first set point with a powerful groundstroke which Jannik Sinner can't get back.
*Sinner 5-4 Djokovic
We're 38 minutes into the semi-final and Jannik Sinner has two chances to take the first set.
*Sinner 5-4 Djokovic
Harry Poole
BBC Sport at Wimbledon
The remarkable defensive capabilities of these two is the perfect foundation for countless enthralling exchanges whenever they meet.
Novak Djokovic let out a huge cry as he did his best to get his racquet behind another booming Jannik Sinner forehand, as the Italian began moving through the gears.
The crowd could not believe Sinner missed that overhead - but the noises of disbelief are quickly replaced by cheers of appreciation as the world number one forces the breakthrough.
*Sinner 5-4 Djokovic
Andrew Castle
BBC Sport tennis commentator on BBC One
This is clearly the best Jannik Sinner has played in this tournament so far.
This is clinical.
*Sinner 5-4 Djokovic
Image source, Getty ImagesThere's the break!
A dream of a backhand pass down the line earns Jannik Sinner a 5-4 lead and he'll now serve for the first set.
Sinner 4-4 Djokovic*
Pat Cash
Former Wimbledon champion on BBC Radio 5 Live
He should have let that bounce. it was right up in the sky, he had time.
Such small margins in this match.
Sinner 4-4 Djokovic*
Oooof - a big chance missed.
Jannik Sinner just had to put an overhead away to break serve but plonks it into the net.
One more break point to come...
Sinner 4-4 Djokovic*
Maybe another chance for Jannik Sinner at 15-30?
It may well be - the Italian drills a cross-court backhand and Novak Djokovic returns it wide.
Two break points...
Sinner 4-4 Djokovic*
Still on serve in the first set, with just the one break point which Jannik Sinner was unable to take in the fifth game.
Sinner shows his proficiency at the baseline and at the net on his way to levelling the set.
Fernandez 7-6 (7-2) 0-6 1-4 Hewett*
Image source, PA MediaAlfie Hewett pumps his fist after saving two break points on his serve to claim a crucial hold and maintain his third set advantage.
He is pulling Gustavo Fernandez all over the court, one way then the other on the baseline, and roars with delight again as he breaks the Argentine again.
Hewett is now on the verge of a sixth Wimbledon singles final.
*Sinner 3-4 Djokovic
Pat Cash
Former Wimbledon champion on BBC Radio 5 Live
Djokovic has had a couple of days [to recover]. I don't see it as a problem. It is a lot of tennis but he is just remarkable in how he is able to recover. We will see, it is warm and sunny out there.
He does play possum a little bit, looks like he's about to drop dead and shake hands but then gets back up and carries on.