MELBOURNE, AUSTRALIA - JANUARY 16: Maria Sharapova of Russia plays a backhand in her second round match against Karin Knapp of Italy during day four of the 2014 Australian Open at Melbourne Park on January 16, 2014 in Melbourne, Australia. (Photo by Cameron Spencer/Getty Images)

Melbourne – Russia's Maria Sharapova overcame sweltering conditions and a stubborn Karin Knapp of Italy to reach the Australian Open third round on Thursday with a 6-3 4-6 10-8 victory.

Sidelined from the latter part of last season with an injury to her right shoulder, the third seeded Sharapova had trouble with her serve with Knapp breaking six times while the Russian made 12 double faults in temperatures in excess of 41 Celsius.

Organisers invoked the Extreme Heat Policy during the final set of the match but the rules meant the roof on Rod Laver Arena could not be closed until the set, and match, had ended.

The second round match concluded about 50 minutes after play had been suspended on all of the outside courts.

“I remember being really close to passing out but I'm feeling much better now,” Sharapova said in a courtside interview about the sweltering conditions. “I think I'm just getting numb to it.

“The recovery's going to be pretty important now.”

The 26-year-old Italian, who had never beaten a top-10 player in her 12-year career, had looked to be in trouble early against the third seed's powerful ground strokes but gradually wore the Russian down.

While her serve was an issue, the 2008 champion's greatest problem appeared to be her inability to temper her impulse to blast winners on every shot, which resulted in 67 unforced errors.

She had looked to have swung the momentum early in the third set when she successfully challenged a line-judge's call after her blistering backhand return at 15-30 in the third game was called out.

The Russian immediately challenged and tracking technology showed the ball had kissed the tramline giving her two break points, the first of which she converted to take a 2-1 lead.

Sharapova then held serve to open a 3-1 lead and while Knapp battled, the Russian looked to have the match in the bag when she held three match points while serving for victory in the 10th game, only for the Italian to storm back.

Knapp then held the advantage with Sharapova twice forced to hold serve at the end of the court that was badly effected by the sun upsetting both players' ball toss.

Sharapova, however, managed to get three break points in the 17th game of the deciding set that she managed to convert to give her a second opportunity to serve for the match.

The Russian again had issues with her serve, producing three double faults, before she sealed the win in three hours, 28 minutes to set up a third round clash with 25th seed Alize Cornet of France.

“It was tough for both of us,” Sharapova said.

“Quite honestly she played some of the best tennis I'd seen her play.” – Reuters