London: Novak Djokovic fought back from a set down to beat Andy Murray 4-6, 6-3, 7-5 at the ATP World Tour Finals on Wednesday and all but sealed a place in the last four of the season-ending tournament.
Murray produced a dazzling first set against the world number one but could not sustain it as Djokovic moved clear at the top of Group A.
Should Jo-Wilfried Tsonga defeat Tomas Berdych in the day’s other singles Djokovic would be assured a semi-final berth with one round-robin match to play.
World No. 3 Murray conceded a mere three points on his serve in a dominant first set but Djokovic got a foothold into the match when he broke the Murray serve for the first time in the sixth game of the second.
Djokovic struck first in the deciding set and had two points for a double break of serve, only for Murray to roar back to 4-4. The Scot then undid all his good work to drop his serve at 5-5 and Djokovic sealed victory after two hours 34 minutes.
In doubles, Mahesh Bhupathi and Rohan Bopanna won their first Group B match with a 6-3, 5-7, 10-5 win over Robert Lindstedt and Horia Tecau to keep their semi-final hopes alive, while Leander Paes and Radek Stepanek also made a winning start.
In a Group A match, third seeds Paes and Stepanek began their campaign with a 6-4, 7-5 win over seventh seeded pair of Aisam-ul-haq Qureshi and Jean-Julien Roger, on Tuesday.
In singles, David Ferrer dipped into his seemingly endless tank of stamina to beat Juan Martin del Potro. The towering Argentine will testify to that after he lost a fascinating duel 6-3, 3-6, 6-4 in front of a packed audience at the 17,000 O2 Arena alongside the River Thames.