Serena Williams has withdrawn from the upcoming Bank of the West Classic tournament because of an elbow injury.
The world number one also withdrew from the Swedish Open two weeks ago, citing the elbow as the problem.
Williams expressed her disappointment in a statement, saying: "The tournament is one of my favorites, and the fans have always been so generous and supportive of me."
Fifth-ranked Caroline Wozniacki is now top seed as she makes her Bank of the West Classic debut.
