Third seed Maria Sharapova has survived brutal conditions and remarkable resistance from little-known Italian Karin Knapp to advance to the third round at Melbourne Park in the longest women’s match of the 2014 Australian Open.

Sharapova blew three match points in the ninth game of the deciding set, but hung tough to eventually win 6-3 4-6 10-8 in an epic match lasting three hours and 28 minutes.

The extreme heat policy was invoked early in the one-hour 55-minute final set but it had no effect on the match, with the set completed with the roof remaining open on Rod Laver Arena.

Sharapova, 26, has won each of the four majors once, with her sole Australian Open title coming back in 2008.

Knapp had only won one match in three previous Australian Open campaigns.

The 26-year-old has also never beaten a player ranked in the world’s top 10.

But she came agonisingly close to breaking that duck on Thursday, pushing the Russian to the limit.

“It was tough for both of us,” said Sharapova, who advanced to a third-round clash with No.25 seed Alize Cornet from France.

“We fought as hard as we could.

“Quite honestly, she played some of the best tennis I’ve ever seen her play.

“I think you just get numb to (the heat), it just doesn’t faze you any more.

“I’m happy – these are the matches that you work for.”

The match bore a striking resemblance to one played by Sharapova back in the first round of the 2007 Australian Open, when she was pushed to 9-7 in the deciding set by Frenchwoman Camille Pin in conditions the Russian later described as “inhumane”.

If anything, it was even hotter on Thursday.

After Sharapova had failed to convert any of her three match points at 5-3 in the decider, the tenacious Knapp broke back to level at 5-5.

Games remained on serve until Sharapova broke again in the 17th game.

But the match had one final dramatic twist, with the Russian serving three double faults in the final game before finally closing out the match when Knapp over-hit a backhand.

Her next opponent at Melbourne Park will be French No.25 seed Alize Cornet, who was also pushed to three tight sets on Thursday before seeing off the challenge of Italian Camila Giorgi 6-3 4-6 6-4.

Former world No.1 Caroline Wozniacki from Denmark went the distance before finding a way past American Christina McHale 6-0 1-6 6-2.

No.5 seed Agnieszka Radwanska from Poland had an easier time of it, downing Belarussian Olga Govortsova 6-0 7-5.

Australian wildcard Olivia Rogowska lost 6-4 7-5 to unseeded Ukrainian Elina Svitolina.