Dominika Cibulkova of Slovakia makes a backhand return to Serena Williams of the U.S. during their quarterfinal match at the Australian Open tennis championship in Melbourne, Australia, Wednesday, Jan. 28, 2015. (AP Photo/Rob Griffith)
Dominika Cibulkova of Slovakia makes a backhand return to Serena Williams of the U.S. during their quarterfinal match at the Australian Open tennis championship in Melbourne, Australia, Wednesday, Jan. 28, 2015. (AP Photo/Rob Griffith)