Novak Djokovic beats Milos Raonic 7-6 (8-6) 7-6 (7-5)
Five-time winner Djokovic through to semi-finals
Serbian has won both his group matches
Raonic faces Dominic Thiem on Thursday for second semi-final place
Thiem beat Gael Monfils earlier in the group
Djokovic 7-6 (8-6) 4-4 *Raonic
Hold up. This is not done.
A few punters at the O2 might have to be fished back from the Jubilee Line platform.
Novak Djokovic throws in a stinker of a game and the second set is back on serve.
*Djokovic 7-6 (8-6) 4-3 Raonic
Milos Raonic is swimming against the current here.
He is having to fight hard just to keep his head above water in the second set.
Novak Djokovic takes him to deuce-town before a clanking overhead finally gets Roanic over the line.
Leon Smith
Great Britain Davis Cup captain on Radio 5 live sports extra
Raonic is really being tested here. His intensity has dipped in this game, he's not as sharp.
Image source, APDjokovic 7-6 (8-6) 4-2 *Raonic
Novak Djokovic whips a game from beneath Milos Raonic while the man mountain is still getting his bearings.
A hold to love.
Leon Smith
Great Britain Davis Cup captain on Radio 5 live sports extra
That's such an interesting last few minutes. Raonic breaks, Djokovic is disgusted with himself and hits his racquet against his shoe, but regains his composure and plays a great game.
*Djokovic 7-6 (8-6) 3-2 Raonic
There are diseases that are easier to eradicate than get Novak Djokovic out of a rally.
The Serbian gets his fangs into a point and just won't be shaken off. Milos Raonic tries massive forehands, backhand slice, moving his man from left to right.
But he is always asked to play just one more shot.
And finally the Canadian nets at 15-40 down.
The beginning of the end?
Image source, Getty ImagesLeon Smith
Great Britain Davis Cup captain on Radio 5 live sports extra
That wasn't in the script, but it shows you the fighting qualities that Raonic has. He'd have been dejected after losing the first set and being broken at the start of this one.
Look at the reaction of Djokovic - he belted his racquet against the soles of his shoes.
Djokovic 7-6 (8-6) 2-2 *Raonic
Novak Djokovic goes to the Milos Raonic backhand at 30-30 - but that wing is not the limp limb it used to be.
Raonic redirects the world number two's power down the line and in for a clean winner. Novak Djokovic is left shaking his head.
Djokovic with a kamikaze raid to the net on the break point that follows and this time fortune does not favour the brave.
Raonic - under little pressure - lines up the forehand and slots it away.
Level pegs in the second.
Leon Smith
Great Britain Davis Cup captain on Radio 5 live sports extra
The rallies are starting to get longer but that won't worry Djokovic too much as he tends to come out on top more often than not when that happens.
Image source, Getty Images#bbctennis
John McEnerney: That short partnership with John Mc did Milos no harm at all, he's got a little swagger about him & he's taking it to Novak.
*Djokovic 7-6 (8-6) 2-1 Raonic
Milos Raonic rattles through a service hold to love. There is a dent in that scoreboard though that will take some repairing.
The Canadian has missed four break points so far in this match. If he gets another, he needs to take it.
Djokovic 7-6 (8-6) 2-0 *Raonic
Milos Raonic finds a lovely jagging angle off his backhand to bring up 30-30.
A deep forehand return right up to the baseline is too good for Novak Djokovic and Raonic has his fourth break point of the match.
But once again Djokovic plucks a monster serve out of the quiver just when he needs it.
The tighter the situation, the higher the quality and Djokovic makes good his escape once again.
Image source, ReutersLeon Smith
Great Britain Davis Cup captain on Radio 5 live sports extra
Raonic is good at controlling his emotions and he'll have to call on that now having suffered such a big disappointment in the tie-break, but it's a long way back for him, especially given his previous record against Djokovic.
Image source, Reuters*Djokovic 7-6 (8-6) 1-0 Raonic
Milos Raonic took a long, leisurely bathroom break at the end of the first set.
Is that, along with the shoe-tying mid tie-break, all part of a campaign to show Djokovic that he is not here to be shoved around the O2?
If so, it is not working.
Djokovic feasts on his opponent's disappointment like a death-eater and a cracking second-service return - wide and fast - sees Roanic dump long at 30-40 down.
Piers Newbery
BBC Sport in London
It's not always the case here but this one had a big-match feel to it from the outset, and has not disappointed so far. Huge cheers reverberated around the O2 Arena with every punch and counter-punch, Raonic's all-out attack winning plenty of support from the 17,000 watching.
The Canadian could not have done much more, but after 64 minutes it went the way of 17 of his 18 previous sets against Djokovic. It could be just what the champion needed.
Image source, Reuters*Djokovic 7-6 (8-6) Raonic
Leon Smith
Great Britain Davis Cup captain on Radio 5 live sports extra
You have to give Djokovic credit for taking the set. Raonic probably had the edge throughout but Dkjokovic started to make inroads, mainly on the second serve, on Raonic's huge serve and started to believe in himself that little bit more.
Djokovic 7-6 (8-6) Raonic
Double fault!
Milos Raonic points to the sky, but the video replay cannot save him.
Novak Djokovic, peeved by the time that Raonic took to do up his shoelace on a changeover in the tie-break, is already sat on his stool.
Leon Smith
Great Britain Davis Cup captain on Radio 5 live sports extra
Djokovic has kept his emotions really well and he looks in a very good place, dealing well with the adversity and the pressure.
Image source, Getty ImagesDjokovic 6-6 (7-6) *Raonic
Milos Raonic flogs a forehand wide off a second-serve return. He should have made something of that. As it is he is serving to stay in the match...
Leon Smith
Great Britain Davis Cup captain on Radio 5 live sports extra
This match has really caught fire in this tie-break. It's been a great first set with ebbs and flows but this is the drama that the crowd has been wanting.