Carson, California:Flavia Pennetta capitalized on an error-strewn performance by Maria Sharapova to win their semifinal on Saturday and set up a final against Samantha Stosur at the L.A. Women's Championships.
Pennetta, the tenth-seeded Italian, won 6-2, 4-6, 6-3 as former World's No.1 Sharapova committed 61 unforced errors and 16 double faults.
Stosur moved within one win of her maiden WTA Tour singles title by cruising past Sorana Cirstea 6-3, 6-2.
Sharapova blew a 3-1 lead in the third set, dropping her final three service games as she continued to struggle with her serve in her sixth tournament since returning from right shoulder surgery last year.
Sharapova wore tape on her right shoulder for the first time this week. A double fault set up Pennetta's second match point. Sharapova sent a forehand wide to lose the match and drop to 9-2 in three-set matches this year.
Pennetta, who was runner-up here last year, will face Stosur after the 13th-seeded Australian used her powerful serve to rout Romania's Cirstea.
Sharapova was wildly inconsistent throughout the match, hitting 34 winners to Pennetta's 17. The Russian faced break points in every service game in the third, and only staved them off once. She broke Pennetta to lead 3-1 before the Italian took control.
"I was 3-1 down and I was thinking it was over, but I just tried to fight," Pennetta said. "It was a little bit difficult for me. I started to feel a little pressure. She's a great champion, it was not easy to beat her."
"The serve was a problem for both," Pennetta said. "I was very nervous with my serve because she was returning so well. She started to make a lot of mistakes."
Sharapova, still making her way back to full fitness after a long absence following shoulder surgery, was disappointed in her showing.
"I didn't feel physically fresh from the beginning of the match," Sharapova said. "I was surprised it actually went to the third. I had my opportunities, I just couldn't close it out."
"Am I happy with where it is? Absolutely not," she said. "I feel like there's more work to be done. There's nothing that a basket of balls can't achieve."
Stosur's greatest success has come with a partner, having won 22 career doubles titles - including the French and U.S. Opens - achieved the No. 1 doubles ranking and also earned two Grand Slam mixed titles.
She's enjoying a strong start to the summer hardcourt season, reaching the Carson final a week after her semifinal finish at Stanford that included a win over Serena Williams.
"My whole career I've been trying to get to this point," Stosur said. "It kind of looks like I've done it late, but I don't worry too much about that. I took a little longer to develop."
Stosur has lost in four career singles finals, including one last year in Seoul. A victory Sunday could boost the Aussie into the top 15 for the first time from her current ranking of 19th.
"The last one in Seoul, I got a little bit ahead of myself," she said. "Since then I've gotten a lot better at closing out matches. If I can handle it right, there's no reason I can't do it.
"I've just got to treat it like I have the last four matches here and don't think of it like a final."
Stosur lost just four points on her serve in the first set, dominating with three love games. She earned the only break in the second game, also the only one that went to deuce. The Aussie won 81 per cent of her total service points in the 62-minute match.
Cirstea, a 19-year-old Romanian, was bothered by pain from plantar fasciitis in her right foot, the same problem she had in Friday's win over Agnieszka Radwanska.
"It was bothering me," she said. "She was in good form and if I wanted to beat her I had to be 100 percent. Sam was playing so good, she didn't give me any chances."