Past U.S. Open champion Samantha Stosur has pulled out of the year's last Grand Slam tournament because of an injured right hand.
The U.S. Tennis Association announced the 33-year-old Australian's withdrawal on Friday.
Annika Beck of Germany replaces Stosur in the field for the tournament, which starts Aug. 28.
Stosur hasn't competed since losing her fourth-round match at the French Open to eventual champion Jelena Ostapenko on June 4. Stosur said that day that her right hand was sore and made it difficult to hit forehands or serves.
Stosur won the 2011 U.S. Open, beating Serena Williams in the final. Stosur also was the runner-up at the 2010 French Open.
She is ranked 43rd this week.