World No. 1 star Victoria Azarenka decided to pull out of the $2 million Dubai Duty Free Championships, citing a left ankle injury.

The Belarusian Azarenka suffered the injury during a semifinal match in Doha last week.

"Obviously it's very disappointing, but, I mean, it's life. It's sport. I just have to take care of it and that's it," Azarenka said. "I take a couple of days off just to see and hopefully it will settle down for as long that I don't need to take a scan or anything.

"But I just need to have my peace of mind and probably will still do the same just to make sure there is nothing really serious. But it has to be taken care of right away."

The 22-year-old Azarenka is off to a sizzling 17-0 start this year, which includes three titles. She captured her first-ever Grand Slam championship at the Australian Open last month, which propelled her to the top of the rankings, where she supplanted Danish star Caroline Wozniacki.

Azarenka, who was the 2010 runner-up in Dubai, was last week's big winner in Doha.

Wimbledon champion Petra Kvitova, French Open titlist Li Na and former Wimbledon and U.S. Open runner-up Vera Zvonareva were also forced to pull out of Dubai because of injury or illness.

Lucky-loser Casey Dellacqua replaced Azarenka in the Dubai draw and the Aussie promptly lost to German Julia Goerges 6-0, 6-2 in the second round on Wednesday. Azarenka had received a bye into the second round.

Also on Wednesday, fourth-seeded U.S. Open champion Samantha Stosur saved all nine break points she faced and reached the third round with a hard-fought 6-1, 6-7 (5-7), 6-1 victory over Czech Lucie Safarova on the hardcourts at Dubai Tennis Stadium. The Aussie Stosur lost to Azarenka 6-1, 6-2 in last week's finale at the Qatar Open.

In other action involving seeds in Dubai, No. 5 Pole Agnieszka Radwanska downed Israeli Shahar Peer 7-5, 6-4, No. 8 Serb Jelena Jankovic handled Italian Flavia Pennetta 6-4, 6-2, and No. 9 German Sabine Lisicki whipped Czech Iveta Benesova 6-3, 6-3. The former No. 1 Jankovic was the Dubai runner- up in 2005.

Meanwhile, another former world No. 1 Serb and former French Open champion, Ana Ivanovic, got past Russian Maria Kirilenko 6-2, 7-6 (7-4) on Day 3.

The reigning Dubai titlist and former No. 1 Wozniacki is also on Wednesday's schedule, as the Dane will take on Romanian Simona Halep. Wozniacki topped Russian Svetlana Kuznetsova in last year's finale here.

The 2012 Dubai champ will earn $446,778.