- Caroline Wozniacki beaten in opening round
- Former world No.1 loses to Kazakhstan's Yulia Putintseva
- Serena Williams sees off Camila Giorgi
- Novak Djokovic and Roger Federer both through to second round
(CNN)Serena Williams and Caroline Wozniacki might be the best of friends but the pair could scarcely have had more different experiences on the Australian Open's first day.