Victoria Azarenka at risk of not securing a top-16 seed at U.S. Open

MASON, Ohio -- Defending champion Victoria Azarenka has withdrawn from the Western & Southern Open with a right knee injury. Azarenka injured the knee after

MASON, Ohio -- Defending champion Victoria Azarenka has withdrawn from the Western & Southern Open with a right knee injury. Azarenka injured the knee after taking a bad fall in her opening match last week at the Rogers Cup in Montreal, where she lost to eventual champion Agnieszka Radwanska in the quarterfinals. 

Azarenka, who has been practicing in Cincinnati with heavy taping around her right knee, practiced on Tuesday morning before deciding to abandon the tournament.

"I tried to recover as much as possible," she said. "I started to feel a little bit better and did everything I could, but it's just not enough time for me to feel good to play a full match." 

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​Azarenka now has two weeks to recover for the U.S. Open, the final Grand Slam of the season, which begins on Aug. 25. Azarenka came into the Western & Southern Open at No. 10 in the WTA rankings, but is now at risk of not securing a top-16 seed at the U.S. Open.

With Li Na's withdrawal from the U.S. Open, Azarenka can still earn a top 16 seed so long as she has a ranking of No. 17 on Monday. The players trying to chase her down this week are Lucie Safarova, Ekaterina Makarova, Andrea Petkovic and Venus Williams, all of whom could pass Azarenka this week depending on their results in Cincinnati.

"I'm going to get more treatment and get more work done and should be good for the U.S. Open," Azarenka said. "But I had to make this decision. I feel strongly that it's the best for me at this moment." 

Azarenka has struggled with fatigue and injury since making the U.S. Open final last year, where she lost in three sets to Serena Williams. She finished the 2013 season with a 1-4 record, but had a strong start to '14 before injuring her foot. Aside from a brief comeback at Indian Wells in March, the former No. 1 did not play a match for over four months, having skipped the clay court season and returning in June at Eastbourne.