Kim Clijsters hit the ball so hard, it almost landed in the top deck of Ariake Colosseum. She had just hit a forehand beyond the baseline and her opponent, Jelena Dokic, instinctively returned the ball to Clijsters' side.

Frustration was mounting with each mistake. The chair umpire gave Clijsters a warning for her behavior, but the one shot that never landed on the court became the momentum-changer in the semifinals for the No. 3 seed in the Toyota Princess Cup on Saturday.

"That was out of frustration. I didn't know what I was doing, but after that my play got better," said Clijsters, who earned the who-wants-to-stand-in-for-Venus prize with a 5-7, 6-2, 6-3 victory over No. 2 seeded Dokic.