World's second best tennis player Rafael Nadal of Spain was eliminated Wednesday in a shocking fourth-round upset from a #54 Russian Michail Youzhny at the U.S. Open championship.

Rafael Nadal admitted he was overwhelmed by 24-year old Moscow-born Youzhny, who recorded 49 winners compared to just 23 for the reigning two-time French Open champion. 

"I know I lost a big opportunity," Nadal said. "Mikhail is playing unbelievable — all winners."

The match turned in the third set when Youzhny battled back from 0-40 to save three set points and hold serve at 5-5, with a sensational win 6:1 over Nadal in fourth set.

"It was a very tough match," Mikhail Youzhny said. "I cannot believe I beat Rafael in four sets."

In meanwhile, top-seeded Roger Federer of Switzerland easily advanced to the quarter-finals, defeating France's Marc Gicquel, while Maria Sharapova won over Tatiana Golovin, Russian-born France-based player.