Reigning Serena Williams champion the latest top seed to fall . World No . 145 loses in straight sets to world No . 145 `` I think she played really unbelievable tennis , and she put a lot of balls back , '' Kvitova said . Novak Djokovic . Serena Williams through to last 16 following win over Varvara Lepchenko . Novak Djokovic and Novak Djokovic through to last 16 in men 's draw .
Reigning Serena Williams champion the latest top seed to fall . World No . 145 loses in straight sets to world No . 145 Novak Djokovic . Serena Williams through to last 16 following win over Varvara Lepchenko . Novak Djokovic and Novak Djokovic through to last 16 in men 's draw .