Playing with tape on her troublesome right shoulder, the unseeded Sharapova hung on to join top-seeded Dinara Safina and defending champion Ana Ivanovic in the next round.
“Obviously I am spending a little bit more time out there than I want to, but I think I’m learning so many new things, as well,” Sharapova said. “I think this was a great match where I had to fight my way through many, many challenges. And I did.”
Venus Williams lost the first set to Lucie Safarova 7-6 (5) before play was suspended because of darkness.
Sharapova, a three-time Grand Slam champion who has slipped to No. 102 in the rankings because of her injury layoff, won five straight games to close out the first set.
Trailing 4-2 in the deciding set, she broke the 11th-seeded Petrova to get back on serve at 4-4, and then saved two break points to take a 5-4 lead. She saved another break point while serving at 6-6.
“I got off to a really good start,” Sharapova said. “I kind of started stumbling away. Things went in the wrong direction. I was just glad I could pick myself up and keep fighting and do the right things, and end the match with a win.”
Sharapova is making her first Grand Slam appearance in almost a year after missing both the U.S. Open and the Australian Open because of her shoulder injury. She had surgery in October.
Safina easily beat 18-year-old Russian qualifier Vitalia Diatchenko 6-1, 6-1, and Ivanovic defeated Tamarine Tanasugarn of Thailand 6-1, 6-2.
Safina took a 5-0 lead to open the match, stretching her streak to 17 straight games after winning 6-0, 6-0 in the first round.
“Pretty good start for the tournament,” said Safina, who lost in the Australian Open final and was the runner-up at Roland Garros last year. “I just played a good game today, good enough to win.”
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Ivanovic looked more comfortable on court after struggling in her opening match. The eighth-seeded Ivanovic broke the 32-year-old Tanasugarn twice in the first set and three times in the second.
“I just want to sort of get my way through the rounds and just feel more comfortable match after match,” Ivanovic said. “Today I think I served some aces, which gave me some confidence in my serve, and that’s something I’ve been working on.”
The 21-year-old Serb finished with three aces.
No. 9 Victoria Azarenka of Belarus also made it through, while No. 21 Alize Cornet of France reached the second round. No. 15 Zheng Jie of China lost.
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