PARIS -- Everything came so quickly for Maria Sharapova at the start of her tennis career. Wimbledon champion at 17. Ranked No. 1 at 18. Second major title at 19, third at 20.
Surgery on her right shoulder in October 2008 put a halt to all of that. Getting her game back in order required patience. And with a 6-0, 6-3 victory over 15th-seeded Andrea Petkovic of Germany on Wednesday, Sharapova reached the French Open semifinals, the first time she's made it that far at any Grand Slam tournament in more than three years.
"There's no doubt there's tough moments. I don't think without tough moments the good ones would feel so good," the seventh-seeded Sharapova said. "I have certainly put in a lot of work, and I was never hesitant. I always tried to push myself as much as I could."
The owner of titles from the other three major tournaments, a championship at Roland Garros would make Sharapova the 10th woman to complete a career Grand Slam.
In the semifinals Thursday, she'll face No. 6 Li Na of China, who advanced by beating No. 4 Victoria Azarenka of Belarus 7-5, 6-2. Li was the runner-up in January at the Australian Open, where she became the first Chinese player to reach a Grand Slam final.
Both Sharapova and Li have are much more comfortable on hard courts than clay, where hard shots are slowed, and the footing required can be rather tricky. Back in 2007, the only other year Sharapova made it to the French Open semifinals, she famously described sometimes feeling like "a cow on ice" when first getting to the clay-court portion of the season.
The French Open is the only major tournament where Sharapova has never reached the final. She entered Wednesday with a 1-3 record in quarterfinals at Paris and 9-0 in quarterfinals at the other three Slams, although she hadn't won one anywhere since the Australian Open in January 2008.
But the 24-year-old Russian won the first eight games against Petkovic, who didn't get on the scoreboard until 52 minutes had elapsed.
"She played flawless in the first set," Petkovic said. "Normally you expect Maria to give you more free points. She didn't at all."
After breaking Sharapova's serve to make it 2-all in the second set, Petkovic let out a yell and pounded her right fist on her chest.
Petkovic then broke again to make it 3-all. Yet she didn't win another game.
It wound up as the 10th consecutive victory for Sharapova, who won her biggest clay-court title at Rome in May.
"There's no doubt that I've improved on this surface," she said. "There's no doubt ... as the years went on, that I felt better and better."
Before now, Li's best performance in Paris was getting to the fourth round in 2009. She lost to Sharapova, who's won five of their seven career meetings.
But Li was steady as can be against Azarenka, compiling nearly twice as many winners, 21-11.
"After I win the match I was feeling, 'Wow! I can play semi in Roland Garros,'" Li said. "I never think about that before. So many people think I'm not so good in clay court, but I think now they should change a little bit."
The 29-year-old Li lost her opening matches at the four tournaments following the Australian Open. But she rebounded once the tour turned to clay, reaching the semifinals in Madrid, Rome and now Paris.
"After the team (said) ... 'Yeah, you can play clay court,'" Li said, "I was like, 'Oh, really?'
"I know I win many matches in the clay court, but I still didn't believe I can play clay court," she said.
Against Azarenka, who had been the highest seeded player remaining in the tournament, Li committed 18 unforced errors, five less than her opponent. She also converted five of her 11 break points while saving three of the five she faced.
"She was a better player today," said Azarenka, who is 0-4 in Grand Slam quarterfinals. "She played very well in the important moments."
Li looks to continue her success on clay.
"You have to slide a lot. Also you have to play a lot of topspin," Li said. "But after this time, I think all Asia people have more confident play in clay court."
In the other women's semifinal, No. 5 Francesca Schiavone of Italy, the defending champion, will play No. 11 Marion Bartoli of France. They won quarterfinals Tuesday. Bartoli is only the fourth Frenchwoman in the Open era, which began in 1968, to get this far at Roland Garros.
Information from The Associated Press was used in this report.