Serena Williams revived memories of her two Australian Open titles by coming from a set and a break down to beat Russian fifth seed Nadia Petrova 4-6 7-5 6-3 and book a place in the fourth round on Friday.

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Williams, champion in 2003 and 2005, looked to be a spent force as Petrova won the first set and recovered from 3-1 down in the second to serve for it at 5-4.

But Williams, unseeded after a catalogue of injuries blighted her 2006 campaign, broke back and won the second before breaking in game six of the decider to set up victory in two hours and five minutes on Rod Laver Arena.

"I really had no other option than for my game to go up," the former world number one told a news conference after her third victory over the Russian at Melbourne Park.

"I was on the verge of going out of the tournament and I did not want that to happen. I felt like I was playing well, but I was not making my shots."

Petrova was 5-3 up in the second set and looked poised to progress, but Williams held serve and the Russian had no answer as the American upped her game and broke before taking the match into a decider.

Williams broke early for a 3-1 lead, but Petrova refused to give up, immediately breaking back, but Petrova's serve let he down again to allow the seven-times grand slam winner to take a 4-2 lead which she never relinquished, sealing the match with her 11th ace.

Petrova's preparation for the tournament had not been ideal, pulling out last week's Sydney International due to stomach cramps, but the Muscovite was offering no excuses.

"She raised her game," a deflated Petrova told reporters. "She started putting more pressure on me and I did not serve great today. I was serving for the match, but she came up with some unbelievable returns."

The win set up a possible fourth-round clash with in-form Serb Jelena Jankovic.

"She's playing really well," Williams said. "I think she's a very solid player so I'm going to have to be playing even better."