Serena Williams won't defend her title at the Bank of the West Classic.
The world's No. 1 player withdrew from the Stanford-based tournament on Friday, citing an elbow injury. That's the same issue that led to her withdrawal from the Bastad tournament two weeks ago after a first-round victory.
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"I'm disappointed to have to withdraw from Stanford, but I need to get my elbow back to 100 percent," Williams said in a statement. "The tournament is one of my favorites and the fans have always been so generous and supportive of me. I wish all of the players much success and I hope to return next year."
Williams, 33, won the Bank of the West the last three times she entered it, in 2011, 2012 and 2014. But her focus now is on getting healthy ahead of the U.S. Open, which begins Aug. 31.
Williams currently holds all four major titles after winning Wimbledon earlier this month and with a title in New York would become the second woman to complete a calendar-year Grand Slam in the Open Era. Steffi Graf did it in 1988.
