Ana Ivanovic of Serbia celebrates a match point won over Samantha Stosur of Australia during their third round match at the Australian Open tennis championship in Melbourne, Australia, Friday, Jan. 17, 2014.(AP Photo/Aaron Favila)
Novak Djokovic of Serbia makes a forehand return to Denis Istomin of Uzbekistan during their third round match at the Australian Open tennis championship in Melbourne, Australia, Friday, Jan. 17, 2014.(AP Photo/Andrew Brownbill)