Roger Federer pushed to five-sets by Gilles Simon

(GETTY IMAGES)

Roger Federer finally overcame his nemesis Gilles Simon tonight although it took him five enthralling sets to reach the third round of the Australian Open.

Simon came into the contest having beaten the world number two on their previous two meetings and he looked set to cause another huge upset when he hit back from two sets down to take it all the way.

But the Swiss, a record 16-time grand slam winner and defending champion in Melbourne, upped the tempo to squeeze through 6-2 6-3 4-6 4-6 6-3 and avoid his first exit at a grand slam before the third-round stage since the 2003 French Open.

The match was delicately poised until Federer broke in the decider for a 4-2 advantage which quickly became 5-2.

The world number two wasted four match points as Simon indulged in one final act of defiance but there was to be no reprieve as Federer sent down a booming ace out wide to set up a third-round clash with Belgian Xavier Malisse.

"He (Simon) is a great player," said Federer.

"Matches against him don't come easy, every time we go the distance. Hopefully we won't play each other anymore.

"I am happy to get through, just keep moving on in the draw and try to find an opponent who suits me more.

"I thought the match was great, it was played at a very high level for a long time, I thought I played great and am very happy."

Simon felt the point at which his comeback stalled arrived at the start of the final set.

"At the beginning of the fifth he played a very good game," said the Frenchman. "We were one-all 0-30 on his serve and he played four good points in a row.

"And from there he did much better on his serve and the second shot.

"There aren't too many players who can go longer than me but Roger is one of them.

"I am just sad I had to play Roger at this stage of the tournament because I was feeling good."

Novak Djokovic also toiled before seeing off Croatian Ivan Dodig.

The third-seed laboured through the opening two sets as Dodig held his own before finally upping his game to record a 7-5 6-7 (8/10) 6-0 6-2 victory in two hours and 21 minutes.

It was a baffling display from Djokovic. Normally such an effervescent character on court, for long periods he looked out of sorts and disinterested, allowing a player 78 places below him in the rankings to dictate the play.

"Maybe the positive thing about this match is I was challenged, pushed to the limits in the first two sets and stayed around three and a half hours on the court," said Djokovic, who will play countryman Viktor Troicki next.

"In the first two sets I wasn't happy with the way I was playing.

"It definitely wasn't my best but in the third and fourth it was okay.

"It's tough to say why, everything is okay but sometimes your legs aren't listening to you."

Fernando Verdasco saved three match points on his way to a stunning victory over Janko Tipsarevic.

The Spanish number nine seed looked to be on his way home at two sets down and again when Tipsarevic served for the contest in the fourth set when leading 6-5. But Verdasco hung in there - saving one of the match points with a stunning running pass down the line from way out of the court - and eventually came through 2-6 4-6 6-4 7-6 (7-0) 6-0.

"Every time you win a match like this it is good for your confidence, to see that you are good physically and mentally," said Verdasco.

"I just kept fighting all the time, my mentality was key."

Verdasco will now meet Kei Nishikori, the young Japanese beating Germany's Florian Mayer 6-4 6-3 0-6 6-3.

Andy Roddick, the eighth seed, overcame a tight first set to see off Igor Kunitsyn 7-6 (9/7) 6-2 6-3 and the American was pleased to have got through in a little over two hours.

"It could have got uncomfortable today if that first set had got away," he said.

"You always try to convince yourself it is a good thing to get through a tough set like that but going into the match, if you're given an option, you want it to be as easy as possible every time."

Tomas Berdych, the 2010 Wimbledon finalist and sixth seed, needed four sets to beat Germany's Philipp Kohlschreiber 4-6 6-2 6-3 6-4, as did 17th seed Ivan Ljubicic in his 6-3 6-7 (2/7) 6-4 7-6 (7/5) win over Benoit Paire.

Berdych will meet 28th seeded Frenchman Richard Gasquet next. Gasquet today beat countryman Adrian Mannarino in straight sets.

Gael Monfils, who is seeded 12 at Melbourne Park, overcame Frederico Gil in four sets while Nicolas Almagro edged out Igor Andreev 7-5 in the fifth.

Mardy Fish is out, though, after losing to Spain's Tommy Robredo. The 16th-seeded American started well before Robredo upped his game to go through courtesy of a 1-6 6-3 6-3 6-3 triumph.