Novak Djokovic of Serbia returns a shot during the men's singles match against Andy Murray of Britain at the ATP World Tour Finals in the O2 Arena in London, Britain, on Nov. 7, 2012. Djokovic won 2-1. (Xinhua/Wang Lili)
Novak Djokovic of Serbia returns a shot during the men's singles match against Andy Murray of Britain at the ATP World Tour Finals in the O2 Arena in London, Britain, on Nov. 7, 2012. Djokovic won 2-1. (Xinhua/Wang Lili)