As first reported by Belgian newspaper De Standaard, two-time defending US Open champion Kim Clijsters has withdrawn from this year's tournament, unable to defend her title in 2011.
The 2011 US Open begins August 29th in Flushing, New York.
Clijsters released a statement shortly after the initial reports came out. "Unfortunately, I will not be able to defend my US Open title this year because of a stomach muscle injury (left rectus abdominus strain)."
"Two weeks of rehab was not enough to heal this injury. Obviously I’m very disappointed. I trained very hard this summer and felt in a good shape to play the US Open."
Matt Cronin of tennis.com reports that Clijsters has also already pulled out of tournaments later this fall in Tokyo and Beijing.
Clijsters initially suffered the abdominal injury last week in Toronto, retiring midway through the second set of her second round match against Zheng Jie, after winning the first set.
Clijsters had previously withdrawn from this week's Western & Southern Open in Cincinnati, at which she was also defending champion.
Clijsters pulled out of Wimbledon in June with a separate ankle injury that she suffered while dancing at her nephew's wedding.
Stay tuned to SB Nation's coverage of the 2011 US Open Series at SBNation.com as well as on Twitter, @DailyForehand .