Stan Wawrinka drops his first set at the Australian Open . Hide Caption 1 of 11 Photos: When Victoria Azarenka upset Caroline Wozniacki in the second round , most would have expected Serena Williams to face the two-time Australian Open winner in the quarterfinals . Serena Williams also rallies , against Garbine Muguruza . Novak Djokovic and Dominika Cibulkova progress to the quarterfinals , too .
Stan Wawrinka drops his first set at the Australian Open . Hide Caption 1 of 11 Photos: Serena Williams also rallies , against Garbine Muguruza . Novak Djokovic and Dominika Cibulkova progress to the quarterfinals , too .