Novak Djokovic of Serbia reacts after missing a shot against Tomas Berdych of the Czech Republic during their group A singles match at the ATP World Tour Finals tennis tournament in London on November... more 
Novak Djokovic of Serbia reacts after missing a shot against Tomas Berdych of the Czech Republic during their group A singles match at the ATP World Tour Finals tennis tournament in London on November 21, 2011. AFP PHOTO / LEON NEAL (Photo credit should read LEON NEAL/AFP/Getty Images) less 
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Getty Images | Photo By LEON NEAL / AFP/Getty Images
Mon, Nov 21, 2011 5:19 PM EST