Sharapova battles hard to advance

Maria Sharapova relied on her famous battling qualities to come out on top in an epic three-setter against Nadia Petrova.

Sharapova has not played a Major since Wimbledon last year because of a shoulder injury, and her ranking of 102 makes her a dangerous floater in the women's draw.

Petrova, the 11th seed, will count herself unlucky to have come up against Sharapova so early after losing 6-2 1-6 8-6 to the former world number one on Suzanne Lenglen court.

Sharapova, a semi-finalist here two years ago, will next play Kazakhstan's Yaroslava Shvedova.

Earlier, top seed Dinara Safina maintained her stunning early form at Roland Garros by making short work of fellow Russian Vitalia Diatchenko to breeze into the third round.

The world number one trounced her compatriot 6-1 6-1 with a performance that was almost as convincing as her first-round defeat of Britain's Anne Keothavong, when she did not lose a game.

"I'm doing the basic things right," said Safina, who could meet reigning champion Ana Ivanovic in the quarter-finals.

"It's a pretty good start to the tournament, a bit different to last year."

Safina was quickly into her stride on Suzanne Lenglen court, breaks in the second and fourth games to open up a 5-0 lead.

Diatchenko, 18, managed to hold serve for the first time in game six but Safina responded to claim the opening set in just 28 minutes.

A stuttering start to the second set by Safina saw the pair exchange breaks in the opening two games but after she regained her composure, it was plain sailing from then on.

"She is very young and maybe she respected me too much," Safina said of Diatchenko.

Anastasia Pavlyuchenkova, the 27th seed and another player from Russia, sealed a third-round date with Safina with a 6-2 7-6 (7/2) win against France's Julie Coin.

Ivanovic is also showing decent form as she bids to defend the title she claimed by beating Safina in straight sets in last year's final.

The Serbian, seeded eighth, swept aside the challenge of Thailand's Tamarine Tanasugarn to win 6-1 6-2 on Philippe Chatrier court and set up a meeting with 32nd seed Iveta Benesova.

"This was a good match to try some things out," said Ivanovic.

"I think my serve is getting more aggressive, which I'm happy about."

The biggest surprise today came on Court Seven, where 15th seed Jie Zheng was upset by Portuguese 16-year-old Michelle Larcher De Brito, a qualifier.

While Agnes Szavay (29) and Na Li (25) were comfortable seeded winners, Belarus' Victoria Azarenka, the ninth seed, was forced to battle before overcoming Kristina Barrois 7-6 (7/1) 7-5.