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 No. 8 seed and Australian Open semifinalist Li Na, who retired from the match because of back spasms.

The unseeded Peer has also beaten top seed Caroline Wozniacki and No. 13 Yanina Wickmayer. She will meet the winner of the late quarterfinal between defending champion Venus Williams and Russian teenager Anastasia Pavlyuchenkova.

"I'm beating so many good players," said Peer. "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."

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 reasons.

The other semifinal will feature Victoria Azarenka against Agnieska Radwanska.

Azarenka had little trouble rubbing out Vera Zvonareva 6-1, 6-3 for the second time in two months. Azarenka beat Zvonareva for the first time 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, and fourth-seeded Azarenka saved seven of nine break points.

Seventh-seeded Radwanska pulled off a comeback against Russian qualifier Regina Kulikova, winning 3-6, 6-4, 6-3 in 2 hours, 18 minutes. Kulikova, ranked No. 99, eliminated French Open champion Svetlana Kuznetsova a day before and showed no fear again, making Radwanska work hard to reach her first semifinals since October.