The signs were there when at 0-4 down Azarenka tossed the ball to serve but missed completely with the ball bouncing off here back.

Temperatures in New York apparently hit above 90 degrees on Monday and look to be higher today. It is yet to be confirmed this was the cause.

In the seventh game after the 10th seed struggled to reach a backhand she collapsed in a heap on the court. A trainer reached her quickly and offered assiatance followed by Azarenka's opponent who crossed the court to help.

Azarenka was eventually helped into a wheelchair and taken off the court leaving Dulko with an unfortunate passage to the third round after 30 minutes.

“It’s a strange, bad feeling,” Dulko said. “In one way, it’s great to get to the third round. In another way, it was not a nice way to win. I really hope she’s O.K. because it looked ugly out there.”