Sharapova survives heat, Knapp's challenge to reach 3rd round at Australian Open

Maria Sharapova of Russia hits a forehand return to Karin Knapp of Italy during their second round match at the Australian Open tennis championship in Melbourne, Australia, Thursday, Jan. 16, 2014.(AP Photo/Aaron Favila) (The Associated Press)

Spectators watch the second round match between Kei Nishikori of Japan and Dusan Lajovic of Serbia at the Australian Open tennis championship in Melbourne, Australia, Thursday, Jan. 16, 2014. (AP Photo/Shuji Kajiyama Shuji) (The Associated Press)

Maria Sharapova survived the searing heat and intense challenge from Karin Knapp to advance to the third round of the Australian Open with a grueling 6-3, 4-6, 10-8 win in 3 hours, 28 minutes on Thursday.

The temperature was forecast to spike at 44 Celsius (111) on the third straight day of a heat wave. It was already 39C (102F) when No. 3-seeded Sharapova's match started and increased to 42.5C (108.5), forcing organizers to enact the Extreme Heat Policy and suspend matches on outside courts.

Sharapova, playing her second tournament back from extended time off for a right shoulder injury, wore ice vests in every changeover after the third game, draped ice bags over shoulders and poured water over her head.