Ana Ivanovic, Victoria Azarenka advance at Carlsbad

• Ana Ivanovic%2C former world No. 1%2C dropped the first set before rallying for a 4-6%2C 6-3%2C 6-2 victory
• Top-seeded Victoria Azarenka cruised in first match since withdrawing in second round at Wimbledon
• Third-seeded Petra Kvitova and fourth-seeded Roberta Vinci also advanced in straight sets

CARLSBAD, Calif. (AP) — Ana Ivanovic of Serbia advanced to the second round of the Southern California Open on Wednesday, beating defending champion Dominika Cibulkova 4-6, 6-3, 6-2.

The seventh-seeded Ivanovic won nine of the final 11 games. She used a strong ground game to overpower Slovakia's Cibulkova, who is coming off a victory Sunday in the Bank of the West Classic at Stanford.

"As soon as the draw came out I thought it was one of the toughest first-round matches, especially being a seeded player," said Ivanovic, the former top-ranked singles player and 2008 French Open champ. "But I was really happy with my performance. This kind of win obviously means a lot to me."

Top-seeded Victoria Azarenka of Belarus beat Italy's Francesca Schiavone 6-2, 6-3 in the second round. Azarenka was playing her first match since withdrawing from her second-round match at Wimbledon because of knee and hip injuries.

"Just going on the court and competing was so much joy for me," Azarenka said. "I was really playing and happy to be doing something I was training for. ... I don't think about it (injuries)."

Former world No. 1 Martina Hingis was scheduled to come out of retirement for the second time Wednesday night, teaming with Daniela Hantuchova in a doubles match. It will be Hingis' first WTA Tour match since September 2007. The five-time Grand Slam singles champion is scheduled to play doubles with Hantuchova in four tournaments, including the U.S. Open.

Ivanovic, who fired coach Nigel Sears after her second-round loss at Wimbledon, said she has been working on "being consistent and also working on that confidence part. I think it plays a big role. I felt like my game has been there at times but not my confidence."

Third-seeded Petra Kvitova of the Czech Republic and fourth-seeded Roberta Vinci of Italy had no problems in winning their opening matches after receiving first-round byes.

Kvitova advanced to the quarterfinals with a 6-1, 6-2 victory over British teenager Laura Robson. The victory avenged Kvitova's second-round loss to Robson at the Australian Open in January.

Vinci beat American Bethanie Mattek-Sands 6-4, 6-2.

In the late match, fifth-seeded Sam Stosur of Australia beat Kazakhstan's Sesil Karatantcheva 6-4, 6-1 in the second round.