Bothered by swirling winds and a teen's surprising moxie, Maria Sharapova was completely lost.

Agnieszka Radwanska of Poland pulled off the stunning upset Saturday, beating the defending U.S. Open champion 6-4, 1-6, 6-2 by rallying to win the last six games.

Sharapova became the first No. 2-seeded woman to lose before the round of 16 at the Open since Andrea Jaeger in 1981. Her father could barely stand to watch, moving from his front-row perch to a seat farther back in his box during the final points.

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The 30th-ranked Radwanska had a lot to do with Sharapova's undoing. At 18, she played with poise and smarts, creeping closer and closer to the service box and daring Sharapova to try for aces.

"I knew that she hates if somebody is moving on the serve," Radwanska said, her braces gleaming in the sunlight.

Sharapova's serve was her undoing, especially after early faults. She won only 23 percent of her second-serve points.

At 6-foot-2, Sharapova's high toss is particularly susceptible to gusts, the same way popups often blow crazy across the street at Shea Stadium. She frequently stood still, waiting for the wind to subside. Still, she wrecked herself with 12 double-faults.

Playing in the glare of a morning match, Sharapova put on a sun visor early but never found her rhythm. Dressed in white instead of her power red night outfit, the defending champion squandered a 2-0 lead in the third set and finished with 49 unforced errors — she had only 25 in her first two matches.

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