LONDON, ENGLAND - NOVEMBER 04: Novak Djokovic of Serbia talks to the media during previews for the ATP World Tour Finals Tennis at the O2 Arena on November 4, 2012 in London, England. (Photo by ... more 

LONDON, ENGLAND - NOVEMBER 04: Novak Djokovic of Serbia talks to the media during previews for the ATP World Tour Finals Tennis at the O2 Arena on November 4, 2012 in London, England. (Photo by Julian Finney/Getty Images) less