American Serena Williams pulled out due to left knee surgery.
American Venus Williams pulled out due to abdominal injury.

US Open, Withdrawals/Non-Entries:
#2 Serena Williams USA left knee
#5 s4 Venus Williams USA stomach muscle strain
#31 Monica Seles left foot stress fracture
#43 Iroda Tulyaganova UZB
#48 Tatiana Panova RUS
#146 Anna Kournikova lumbar spine strain