New York, Aug 21 - Number one Serena Williams Friday blamed a mysterious summer foot injury with forcing her withdrawal from the US Open.
The American, who has not played since winning the Wimbledon title last month, cut her right foot in Europe - reportedly at a Munich restaurant - under circumstances that have yet to be fully explained.
She underwent surgery and had hoped to be fit for the final major of the season starting a week from Monday.
The 13-time Grand Slam champion lost in the New York semi-finals a year ago to Kim Clijsters in a match in which she threatened a lineswoman over a foot fault and drew a record fine.
"It is with much frustration and deep sadness that I am having to pull out of the US Open," read a statement from Williams. "My doctors have advised against my playing so that my foot can heal."
Williams last missed a slam in 2006 at Wimbledon. (dpa)