Wimbledon champion Petra Kvitova and world No. 2 Kim Clijsters have withdrawn from the Mercury Insurance Open in San Diego, the tournament announced.
Clijsters said in a TV interview on Friday that her injured right ankle had healed and that she had been hitting for more than a week, but apparently she didn't feel like she had enough time to prepare for San Diego, which begin on August 1.
However, Clijsters messaged TENNIS.com on Twitter and said "Ankle is better but not completely healed."
The seventh-ranked Kvitova is suffering from a pulled abdominal muscle.
Both women are scheduled to play the tournament in Toronto the week after San Diego.
San Diego did add the strong German trio of Andrea Petkovic, Julia Goerges and Sabine Lisicki to its field, and still features No. 3 Vera Zvonareva, defending champion Svetlana Kuznetsova and former No. 1 Ana Ivanovic.