

Venus Williams of the US makes a forehand return to Sandra Zahlavova of the Czech Republic during their second round match, which Ms. Williams won, at the Australian Open tennis championships in Melbourne on Jan. 19. Andrew Brownbill/AP
Sandra Zahlavova makes a forehand return to Venus Williams during their second round match at the Australian Open on Jan. 19. Andrew Brownbill/AP
Switzerland's Roger Federer makes a forehand return to France's Gilles Simon during their second round match at the Australian Open on Jan. 19. Andrew Brownbill/AP
Gilles Simon makes a forehand return to Roger Federer during their second round match at the Australian Open on Jan. 19. Andrew Brownbill/AP
Roger Federer shakes Gilles Simon's hand after winning their second round match at the Australian Open early on Jan. 20. Andrew Brownbill/AP
Anne Keothavong of Britain serves to Andrea Petkovic of Germany during their match at the Australian Open on Jan. 19. Mick Tsikas/Reuters
Andrea Petkovic yells during her second round match that she won against Anne Keothavong at the Australian Open on Jan. 19. John Donegan/AP
Frederico Gil of Portugal serves to Gael Monfils of France during their match at the Australian Open on Jan. 19. Yuriko Nakao/Reuters
Gael Monfils hits a return during his victorious match against Frederico Gil at the Australian Open on Jan. 19. Yuriko Nakao/Reuters
Fans of Gael Monfils cheer during his match against Frederico Gil at the Australian Open on Jan. 19. Yuriko Nakao/Reuters
Maria Sharapova of Russia serves to Virginie Razzano of France during their second round match, which Ms. Sharapova won, at the Australian Open on Jan. 19. Rob Griffith/AP
Li Na of China signs autographs after winning her match against Evgeniya Rodina of Russia at the Australian Open on Jan. 19. Yuriko Nakao/Reuters
Spectators watch a second round match between Gael Monfils and Frederico Gil on Margaret Court Arena as the sun sets at the Australian Open on Jan. 19. Vincent Thian/AP