Novak Djokovic of Serbia enters the arena prior to 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 enters the arena prior to 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)