Former champion Stosur out of US Open

Samantha Stosur has withdrawn from the US Open due to the hand injury which has kept the 2011 winner off the court since her fourth-round French Open loss.

Former champion Samantha Stosur has pulled out of this month's US Open because of an injured right hand.

The US 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 on August 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 US Open, beating Serena Williams in the final. Stosur also was the runner-up at the 2010 French Open.

She was ranked No.43 this week and will fall behind fellow Australian Ashleigh Barty, who this week upset Venus Williams in Cincinnati before falling to former No.1 Caroline Wozniacki.

Stosur held Australia's top women's ranking for a record 442 weeks but has now surrendered that crown to Daria Gavrilova.