Andy Murray loses to Stan Wawrinka 7-6 (7-4) 6-4
Wawrinka will face Federer in Saturday semi-final
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Image source, Getty ImagesYou can keep up with all of those matches on this website with added coverage of the first semi-final on BBC Two and of the second on Radio 5 live sports extra.
Two corking matches on one incredible stage.
I'll see you there I presume.
Bye for now.
So tomorrow looks like this at the O2:
14:00 GMT: Rafael Nadal v Novak Djokovic
20:00 GMT: Roger Federer v Stan Wawrinka
And Andy Murray might seek out a little red dirt to hit balls on.
Image source, ReutersAndy Murray speaking to Sky Sports: "The first set tie-break was important,but there are lots of points that go into the outcome. The reality is that I did not play well enough. There were cheap errors on big points and I only have myself to blame."
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Matt Harding, external: Silver lining - if Murray loses he'll be fresher for Davis Cup...
Naveed Afzal, external: Stan has looked angry tonight. That backhand is ferocious tonight. Absolutely ripping it now #bbctennis, external
Image source, Getty ImagesHere are some of the match stats from tonight:
Murray- Wawrinka
Aces:2-4
Double faults:1-4
First serve %:58-45
First serve pts won %:76-75
Second serve pts won %:48-59
Break pts converted:2/10 - 3/5
Image source, AFPStan Wawrinka; "It was tough battle. It was an amazing atmosphere tonight and I am excited to be back for the semi-finals.
"I played a crazy match against Roger in the semi-finals last year and I will try and go and get some rest and be ready."
Murray 6-7 (4-7) 4-6 Wawrinka
Image source, ReutersAndy Murray tosses some sweat bands and his broken racquet to the fans as he marches towards the dressing rooms before the public address can properly bid him farewell.
He will have frustration to take out on the Belgians.
Which is lucky, because he is not bring much form into the Davis Cup final.
Murray 6-7 (4-7) 4-5 Wawrinka*
Image source, AFPAndy Murray saves the match point. Back to deuce...
But the Scot is pressed back once more and will have to fight for his life once more...
Murray 6-7 (4-7) 4-5 Wawrinka
Andy Murray issues himself with a stern telling off as he over-cooks a forehand to allow Stan Wawrinka back to deuce.
A little over-eager.
And Murray smashes the frame of his racquet in disgust as he offers up a match point with a dolly shot that Wawrinka smashes away.
Murray 6-7 (4-7) 4-5 Wawrinka*
Image source, Getty ImagesAndy Murray pops blood vessels and tests his hernia resistance as he silently screams in disgust at an error at 0-30 to the good.
He recovers his composure though to set up 15-40 and two break points.
Murray 6-7 (4-7) 4-5 Wawrinka*
Andy Murray keeps his hand in with hold to love. There was belief stirring somewhere in that game.
Stan Wawrinka has another chance to try and finish this contest on his own tee-off however.
The Swiss has been flaky in the past. A full-blown case of the colly-wobbles needed now for Murray.
*Murray 6-7 (4-7) 3-5 Wawrinka
Image source, Getty ImagesIf this is the start of a comeback, Andy Murray has left it late.
The Scot pumps his fist to the crowd and urges more volume.
He was flatlining in the match. Can that be the game that jump-starts his game?
Murray 6-7 (3-7) 2-5 Wawrinka*
Stan Wawrinka makes his way back to deuce and it is Andy Murray who is standing in the tea-pot pose, staring at his strings and the lines in turn and in disbelief.
Murray 6-7 (3-7) 2-5 Wawrinka*
The wheels suddenly look a little wonky on the Wawrinka wagon.
Murray with three break points at 0-40 after a string of errors from the Swiss.
Murray 6-7 (4-7) 2-5 Wawrinka*
Image source, AFPAndy Murray in a world of pain now.
He will go to bed tonight with nightmares of flashing Wawrinka backhands for company.
Stan serves for the match next.
A severe case of the jitters is the Scot's main hope.
*Murray 6-7 (3-7) 2-3 Wawrinka
Image source, EPAStan Wawrinka is not just demonstrating the textbook to Andy Murray, he is swatting the Scot around the head with it.
A lovely backhand stab on the stretch hugs the line perfectly to put the Swiss 0-30 up.
Murray pumps long on the forehand and folds into a scream of anguish. Break point Wawrinka.
Image source, APStan Wawrinka has struck 24-carat backhand gold.
That glorious one-handed flourish is unfurled to devastating effect. Murray is left groping at thin air.
Wawrinka holds to love. Another two service games like that and he is home and hosed...
Andy Murray breezes through a serve game to love. A bit of respite for the British kingpin.
But he can't bunker down and take cover. He has to come out fighting if he is to hang around beyond tonight in this tour finale.
*Murray 6-7 (3-7) 1-3 Wawrinka
Image source, EPAAndy Murray's eyes stray up to the rafters where his coach Jonas Bjorkman and wife Kim are sitting in the gloom.
His errors return as he strikes a return long off a Wawrinka second serve and then floats a backhand long as the Swiss holds serve.