Novak Djokovic won the latest installment of his thrilling rivalry with Andy Murray as the world number one fought back to secure a dramatic 4-6, 6-3, 7-5 victory in the ATP Tour Finals at London's O2 Arena on Wednesday.
Djokovic has a 100% record after two Group A matches at the season-ending event and will be guaranteed a place in the semifinals if France's Jo-Wilfried Tsonga defeats Czech fifth seed Tomas Berdych later on Wednesday.
World number three Murray now needs to win his final group match against Tsonga on Friday to avoid an early exit after the US Open champion failed to take advantage of a promising start. Djokovic and Murray have been on-court rivals and off-court friends since the day they first faced off at an Under-12s tournament in the south of France.
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 semifinal hopes alive, while Leander Paes and Radek Stepanek also made a winning start at the ATP World Tour Finals.
It was a good comeback for fifth seeds Bhupathi and Bopanna after losing the first match to Jonathan Marray and Frederik Nielse.
In Group A, third seeds Paes and Stepanek began their campaign with a 6-4, 7-5 win over the seventh-seeded pair of Aisam-ul-Haq Qureshi and Jean-Julien Roger. Bhupathi and Bopanna raced to a 3-0 lead by breaking Lindstedt's serve in the second game.