Serbia's Novak Djokovic
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Serbia's Novak Djokovic reacts after a point against Switzerland's Stanislas Wawrinka during their men's singles match on day seven of the Australian Open in Melbourne on Jan. 21, 2013.
Serbia's Novak Djokovic reacts after a point against Switzerland's Stanislas Wawrinka during their men's singles match on day seven of the Australian Open in Melbourne on Jan. 21, 2013.