Tournament organizers say French Open champion Li Na and Vera Zvonareva have pulled out of the Dubai Tennis Championships that start Monday because of injuries.
Organizers did not give details of the players' injuries.
Last week, Zvonareva retired from the Qatar Open while trailing Monica Niculescu of Romania 7-5, 3-2 because of pain in her left hip.
Australian Open champion Victoria Azarenka is the top-seeded player at the Dubai tournament.
The field includes defending champion Caroline Wozniacki, Wimbledon Open champion Petra Kvitova and U.S. Open winner Sam Stosur.