NEW YORK -- France's Mary Pierce and Tathiana Garbin of Italy have withdrawn from the U.S. Open with injuries.

Pierce pulled out because of problems with her lower back. Pierce, the 2000 French Open champion, has reached the quarterfinals of the U.S. Open twice, in 1994 and 1999.

Garbin has a herniated disc. She was hurt at the estyle.com Classic in Manhattan Beach, Calif. Her best result in the U.S. Open came last year, when she reached the third round.

Two stars withdrew from the men's competition Friday -- Dutchman Richard Krajicek and Swede Magnus Norman.

The U.S. Open starts Aug. 27.