DUBAI, United Arab Emirates -- Shahar Peer is proving unstoppable at the Dubai Championships one year after the Israeli was denied a chance to play in the tournament.
Peer beat a seeded player for the third time in four matches and advanced to the semifinals with a 7-5, 3-0 win over Australian Open semifinalist Li Na, who retired from the match because of back spasms.
"I'm beating so many good players," Peer said. "It's really good, and I'm happy by the way I'm playing. I think I'm playing very, very good, and everything is coming together. So I just hope to keep going."
Peer has been surrounded by security and plays on the most secure court at the Aviation Club.
"She's so brave, she's got so much character," Williams said. "I can't imagine playing so well with this kind of circumstance. I don't think anyone else on tour could do what she's doing."
Last year, Dubai organizers were fined $300,000 by the WTA for not allowing Peer to play in the event. She was denied a visa by the United Arab Emirates government, citing security concerns.
After Williams won the tournament last year, she said the decision to defend her title would rest on whether Peer was allowed to play in 2010.
On Thursday, Williams trailed 3-1 before she changed tactics and became more aggressive. She won five straight games to end the first set.
Pavlyuchenkova saved three match points on serve while trailing 5-3, and three more on Williams' serve in the next game.
"I had to play my best tennis to beat her because she was playing so well," Williams said. "She is a very aggressive player and she was hitting it hard."
The other semifinal will feature Victoria Azarenka against Agnieska Radwanska.
Azarenka had little trouble defeating Vera Zvonareva 6-1, 6-3 for the second time in two months. Azarenka stopped Zvonareva en route to the Australian Open quarterfinals and was even more impressive this time.
Zvonareva, winner of seven straight matches including the Pattaya title, was broken six times. The fourth-seeded Azarenka saved seven of nine break points.
Seventh-seeded Radwanska rallied against Russian qualifier Regina Kulikova, winning 3-6, 6-4, 6-3. Kulikova, ranked No. 99, defeated French Open champion Svetlana Kuznetsova the previous day. She showed no fear again, making Radwanska work hard to reach her first semifinal since October.