Novak Djokovic concluded the ATP season on a high note with a victory over Roger Federer.
Novak Djokovic clinched a tense ATP World Tour Finals decider over Roger Federer on Monday, winning the illustrious title in London.
Djokovic beat Federer 7-6 (8-6) 7-5, breaking the Swiss twice in succession late in the second set to complete the 2012 season.
The Serb came into the match looking for his second title win at the season-ending championships, having claimed the event in 2008, but he got off to the worst possible start as Federer broke to love early on his way to a 3-0 lead.
But Djokovic fought back in customary fashion, producing a break of his own to level the opener at 3-3 with a brilliant top-spin forehand winner.
Djokovic would break again three games later to ensure he served for the set at 5-4, but Federer came back from 30-0 down to break for 5-5.
Both players held serve to send the set into a tiebreaker which saw both players produce their best tennis.
Federer saved one set point with a brilliant cross-court forehand but couldn't hold out, as Djokovic rounded out the tiebreaker 8-6 with a forehand winner of his own to take the set after 76 minutes in front of a raucous crowd at the O2 Arena.
The second set mirrored the first with Federer breaking early to go up 2-0 before he raced to a 5-3 advantage. The 31-year-old looked set to take the match into a deciding third set before Djokovic fought back once again, releasing a roar as he squared it at 5-5.
From there, Djokovic held serve before breaking Federer again, winning the title with an aggressive backhand to cap a sensational final in two hours and 14 minutes.
The victory sealed a great year for Djokovic with the 25-year-old winning the Australian Open and reclaiming the world number one spot from the Swiss, while Federer will head into 2013 hoping to add to his record 17 majors.