Azarenka collapses at U.S. Open

The scene was simply scary: Victoria Azarenka, a 21-year-old on the rise in the WTA rankings, paused about a half-hour into her second-round match Wednesday at the U.S. Open, then staggered, stumbled and collapsed to the court.

Azarenka, seeded 10th in the Grand Slam tournament, rolled over to rest her head on her arm, and a trainer rushed over. Someone covered Azarenka's legs with a white towel. She retired from the match, eventually was helped into a wheelchair, her yellow visor askew atop her head, then taken to a hospital, where tests showed she had a mild concussion.

As a record-breaking summer suffocates New York, the temperature in Flushing Meadows headed into the 90s for a third consecutive day, and the mercury topped 100 degrees on court. But tournament referee Brian Early said Azarenka's problem did ''not seem to be primarily a heat-related illness.''

Indeed, Azarenka herself later revealed she fell in the gym while warming up before the match, banging her head and arm in the gym.

''I was checked by the medical team before I went on court and they were courtside for monitoring. I felt worse as the match went on, having a headache and feeling dizzy,'' said Azarenka, who is from Belarus but lives part of the year in Scottsdale, Ariz., with the family of NHL goalie Nikolai Khabibulin, someone she considers a mentor.

Azarenka began wobbling early in her match against Gisela Dulko of Argentina, taking extra time between points and wincing occasionally, clearly in distress. Azarenka said she ''started having trouble seeing and felt weak.''

She is an up-and-comer on tour, part of a group of young players seen as potential future Grand Slam champions. Azarenka beat Maria Sharapova in the final of a hard-court tournament in California last month and pushed Serena Williams to three sets before losing in the Australian Open quarterfinals in January.

Against Serena Williams in the fourth round of the 2009 Australian Open, Azarenka stopped in the second set, dizzy and in tears, and blamed a virus.

Her frightening exit Wednesday caught everyone's attention. Top-seeded Caroline Wozniacki wrote on Twitter: ''Did anyone watch Vikas match?? I really hope she is ok!''

The match was halted with Azarenka trailing Dulko 5-1.

''It was terrible. It's not nice to see someone feeling bad, not nice to win a match this way. I hope she feels OK now,'' said Dulko, who walked around the net to check on the prone Azarenka. ''I was worried for her.''