GAME, SET AND MATCH! - FEDERER 6-4 7-6 SOCK. Federer's bid for a seventh end of season title is off to a solid start following a hard-fought straight sets victory over Jack Sock at the O2. The Swiss takes the TB 7-4 and completes the victory in one hour and 31 minutes.
Roger Federer - Jack Sock
ATP World Tour Finals - 12 November 2017
World Tour Finals – Follow the Tennis match between Roger Federer and Jack Sock live with Eurosport. The match starts at 22:00 on 12 November 2017. Our live coverage lets you follow all the key moments as they happen.
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TB UPDATE: Sock rallies for 4-4 but then double faults. It's 5-4 to Federer with two serves for the Swiss to come...
TB UPDATE: It's 4-2 to Federer at the change of ends. Big ask for Sock now.
TIE BREAK! - FEDERER 6-4 6-6 SOCK. Tie break time! Federer has been completely untroubled on serve throughout and he eases to a love hold. Pressure? What pressure?
FEDERER 6-4 5-6 SOCK. An 11th ace and a crunching crosscourt forehand winner earn Sock the minimum of a tie break after he was once again pushed the distance on serve. Federer's frustration will be growing on the back of another missed opportunity on BP and he must now hold firm to take us to the TB.
FEDERER 6-4 5-5 SOCK. Far too good. Federer surges to a love hold. No problem for the Swiss who hasn't faced a BP yet.
FEDERER 6-4 4-5 SOCK. How many get out jail free cards does Sock have left up his sleeve? The world No.9 makes a succession of unforced errors to give Federer another chance to break from deuce. The Swiss misses with a backhand down the line and then slaps another chance into the net off the same wing. Sock is put through the grinder but survives with big serving to stay alive.
FEDERER 6-4 4-4 SOCK. Roger shrugs off his disappointment with a love hold. Sock went for broke at 40-0 but bulldozed a ferocious forehand just long of the baseline.
FEDERER 6-4 3-4 SOCK. That's a big, big hold from Sock. Federer looks all set to strike a decisive blow at 15-30, but the American refuses to relinquish his serve, forcing it to deuce before keeping his nose in front with a brutal wide ace to finish.
FEDERER 6-4 3-3 SOCK. Once more Federer responds in kind. A slick serve and volley followed by a wrong-footing forehand winner snare the love hold. All square. Who will blink first?
FEDERER 6-4 2-3 SOCK. And there isn't one! Sock's service rhythm is right in the zone as he mixes it up nicely to keep Fed guessing. It's a love hold once again.
FEDERER 6-4 2-2 SOCK. Whatever you can do... Federer rushes through his own hold to 15 to move level. You sense the Swiss is waiting for his moment to pounce here. Sock can't afford any lull now.
FEDERER 6-4 1-2 SOCK. It's a purple patch for Sock. He marauds through another easy hold for the loss of one point. It's impressive stuff. His confidence is clearly on the up as he maintains the scoreboard advantage in Set 2.
FEDERER 6-4 1-1 SOCK. Federer wastes little time with the riposte. This has been a highly competitive match with the occasional sprinkle of truly entertaining moments - but can Sock actually do any damage to the Fed defence to put the final result into real doubt?
FEDERER 6-4 0-1 SOCK. What a contrast between opening service games! That's much better from Sock as he starts Set 2 with a stylish love hold. A drop volley and a well retrieved crosscourt forehand on the scamper do the damage as he gives his own belief a much-needed injection.
SET! - FEDERER 6-4 SOCK. A pair of aces clinch the game to 15 and sees Federer take the opener in just 36 minutes.
FEDERER 5-4 SOCK. It's a love hold for Sock, who hammers down some big serving to breeze through the hold in double-quick time. Over to Roger now to try and serve it out.
FEDERER 5-3 SOCK. Ruthless play from Federer. He races into a 40-0 lead with the new balls. Sock nicks one back, but it merely delays the inevitable as the 19-time Slam champion eases a forehand down Sock's left flank to complete the hold. He's one away from taking the opener.
FEDERER 4-3 SOCK. A nice chuckle between the two players at the end as Sock turns his back at the net, only for Federer to dump a simple pass into the open court into the net. It lets the world No.9 off the hook after he had double faulted to give the Swiss a real opportunity from deuce. Still just the one break in it.
FEDERER 4-2 SOCK. Some positive signs for Sock who must be lamenting that nervy opening service game right now. Federer must have sensed it given he chose to receive first, but it's the Swiss who has to work hard on serve to stay on course here. Sock produces a wonderful pass for 15-30 to pose a question, but Federer gets the job done from deuce with some typically ice-cool tennis under pressure.
FEDERER 3-2 SOCK. When you're playing Roger Federer you can't afford any lapse. Sock looks in total control at 40-15 but double faults to put himself under undue pressure. A quite scintillating return winner forces it to deuce, but to his credit, the American responds with some big serving to stay in contention.
PHOTO: A legend arrives.
FEDERER 3-1 SOCK. Federer shrugs off some early malfunctions with serve to reel off a four points on the spin and maintain his lead.
FEDERER 2-1 SOCK. Jack looks to have settled. He's engaging Federer in some lively exchanges and gets on the board with a bullet forehand down the line to clinch a solid hold to 30.
FEDERER 2-0 SOCK. The Swiss Maestro consolidates, but only after a wobble from 40-15 to deuce. A double fault gives Sock a sniff, but he slaps a very make-able crosscourt forehand into the net before the USA hopeful fires long after a lengthy rally.
BREAK! - FEDERER 1-0 SOCK. A nervy opening from Sock sees him leave himself with too much to do. He fights back from 0-30 but two sizzling winners down the line get Federer off to a flyer. Only one winner here it seems!
Here we go, Sock to serve first...
Sock loses the toss and Federer opts to receive. Time for the warm up!
25-year-old Sock's late surge to book the final spot in London saw him claim his first ever Masters 1000 title with victory in Paris.
Federer's been rather busy in the week leading into the finals. He was, of course, in Scotland for an exhibition match with GB's very own Andy Murray. It was thoroughly entertaining and sent social media onto meltdown when the Swiss Maestro played a game in a kilt!
Federer was in typically gracious form as he accepted no less than three awards at the ATP World Tour Awards that took place on the eve of this tournament.
HEAD-TO-HEAD: The players have only met on three previous occasions with FedEx winning all of them. The most recent was a few months back on the outdoor hard court of Indian Wells where the Swiss booked his spot in the final with 6-1 7-6 success. Indeed, Sock has yet to take a set off the 19-time Grand Slam champion.
Good afternoon and welcome to live updates of the opening singles match of the 2017 Nitto ATP World Tour finals. It's world No.2, Roger Federer against American Jack Sock in Boris Becker group.