Novak Djokovic capped a stunning 2015 season with a dominant display to defeat Roger Federer and claim a record-breaking fourth successive title at the ATP World Tour Finals in London. Djokovic claimed breaks in either set to clinch a 6-3 6-4 victory to win a fifth crown at the season-ending tour finals against an error-strewn Federer.
The Australian Open, Wimbledon and US Open champion had lost the pair's round robin match earlier in the tournament but he cruised to a 22nd career win over Federer with a stunning return to form to end his year in the grand manner. Federer, who had withdrawn with injury from the pair's final last year, failed to rouse himself again.
But Djokovic's 11th title of the year ends a phenomenal year for the Serbian, who lost just six times and failed to reach a final in a tournament he entered only once during the last 12 months. Recovering from defeat to Federer earlier in the week, Djokovic has sent an ominous message to his rivals ahead of the new term, which is also confirmed to start with Andy Murray as world number two.
Not for the first time, ample history hinged on another meeting between Djokovic and Federer in the finale to the ATP season. An unprecedented fourth straight title was tantalising close for Djokovic while Federer was chasing a seventh crown at the season-ending tour finals.
Federer had won their round-robin encounter in straight sets to keep Djokovic - who suffered his first defeat since August - from going ahead in the head-to-head. But having gone on to complete comfortable wins over Tomas Berdych and Rafael Nadal it had not had an adverse affect on the defending champion.
Both players saved a break point in their opening service games, the pair capitalising on their opponent find the net on the forehand side. Djokovic flashed a backhand cross-court to bring up another chance to break, which he took as Federer found the net again.
Having converted just four out of 23 break-point chances at the US Open, Federer's cutting edge on Djokovic's serve would again be crucial but those demons from Flushing Meadows returned a backhand went long with the opportunity to level the set at his mercy. That missed opportunity would come back to haunt Federer as when faced with serving to stay in the set a tame backhand found the tramlines to put Djokovic into the ascendency.
Djokovic's telescopic reach had nullified Federer's tactic of exchanging baseline blows and though the Swiss rediscovered his consistency, his game continued to be littered with errors. In game eight, a netted forehand from Federer was followed by successive backhand and forehand winners from Djokovic to put himself within touching distance of another break.
Five points in a row kept the match alive but a love service hold put the pressure back on Federer - and the 17-time grand slam champion wilted under the strain. A lengthy rally lasting 32 shots put Djokovic 0-30 up before Federer netted a volley to bring up two match points. An anti-climatic final was given an apt finish as Federer double faulted to give Djokovic the title to clinch yet another title.