Former U.S. Open champion Samantha Stosur pulled out of this year's tournament due to an injured right hand, the U.S. Tennis Association announced Friday.
Stosur hasn't competed since the French Open in June due to the injury. The Australian said the injury is hampering her serves and forehands.
Stosur posted a memorable upset in the 2011 U.S. Open final when she defeated Serena Williams in straight sets.
Germany's Annika Beck was tabbed as a replacement.
The U.S. Open begins on Aug. 28 in New York.