Charleston:Top-seeded Elena Dementieva of Russia advanced to the Family Circle Cup semifinals when Slovakia's Dominika Cibulkova quit in the second set Friday because of a leg injury.
Dementieva next meets fifth-seeded Caroline Wozniacki of Denmark, who routed Frenchwoman Virginie Razzano 6-2, 6-0.
German Sabine Lisicki, the 16th-seed who ousted Venus Williams on Thursday, advanced with an easy 6-4, 6-0 victory over unseeded Russian Elena Vesnina. She will face sixth-seed Marion Bartoli of France, who easily eliminated Hungary's Melinda Czink, 6-4, 6-1
Dementieva won the first set 6-4, and was up 1-0 in the second against Cibulkova in a match featuring long baseline rallies. Cibulkova, seeded seventh, played with her left thigh wrapped and had it rewrapped between sets before retiring. She waved to the crowd as she walked off the green clay.
A tour spokesman said that Cibulkova's leg had been wrapped because of a left adductor, or groin, injury.
Cibulkova led 4-3 in the first set before Dementieva won three straight games, surrendering only three points. She is 3-1 against Cibulkova.
"She came with the tape on her leg and I didn't know if it was bad or not, so I just feel sorry she couldn't finish the match," Dementieva said.
Wozniacki, an 18-year-old Dane, won last week on clay at Ponte Vedra Beach, Florida. She said she wants to enjoy her victory and think about Dementieva on Saturday morning.
"I need to stay aggressive," she said. "My legs have to be there, too. I need to keep running because she's a great player, great fighter."
After trailing early, Vesnina tied Lisicki at 3-3 in the first set. But then she could only win one more game against the German with a powerful serve. Lisicki steadily served at well over 100 mph (160 kph), including five aces.
"I think I served pretty well," the 19-year-old Lisicki said. "In the beginning, I couldn't serve the whole time very good. I made some double faults."
She called it the best tournament of her career.
"I'm really happy with it. And I've beaten Williams so it's a great tournament for more," she said.
Cibulkova's retirement was the second by a seeded player in two days. Razzano advanced Thursday night when third-seeded Vera Zvonareva injured her ankle chasing a ball and left the stadium in a golf cart.
Bartoli, who has won all three of her Family Circle matches in straight sets, said it was good to be in the semis and it will help as she prepares for coming weeks.
"My goal is to play really well at the French Open, that's why I'm starting the clay season so early," she said, adding she beat Lisicki last year at Wimbledon.
"But you know, she beat Venus here and she's in the semifinal as well," Bartoli said. "It's going to be difficult, but if I'm playing the same way as I played tonight, it's going to be a great match."
Cibulkova's retirement was the second by a seeded player in two days. Razzano advanced Thursday when third-seeded Vera Zvonareva injured her ankle chasing a ball and left the stadium in a golf cart.