Caroline Wozniacki of Denmark hits a backhand return to Christina McHale of the U.S. during their second round match at the Australian Open tennis championship in Melbourne, Australia, Thursday, Jan. 16, 2014.(AP Photo/Eugene Hoshiko)
Caroline Wozniacki of Denmark hits a forehand return to Christina McHale of the U.S. during their second round match at the Australian Open tennis championship in Melbourne, Australia, Thursday, Jan. 16, 2014.(AP Photo/Aaron Favila)