SEVILLE, Spain Olympic Champion Ji Xinpeng of China was sent crashing out of the World Badminton Championships here wednesday, losing in three games to unheralded Hong Kong player Agus Hariyanto.

Ji, seeded 11 for the tournament, was beaten 12-15, 15-11, 15-4 by the Hong Kong youngster in a stunning second round upset at the San Pablo Stadium.

The Chinese star never got going against Indonesia-born Hariyanto, who caused Sydney olympics singles gold medallist Ji no end of problems with some clever variation and teasing drop shots.

The win is the biggest of Hariyanto's career, and the world number 25-ranked hong kong player leapt for joy on claiming the win.

"I can't believe it. I knew I had a chance, this is the best thing that has ever happened to me in badminton," said Hariyanto, who looked almost as shell-shocked as Ji after the victory.

The 24-year-old player moved to Hong Kong four years ago with his family from Indonesia and has represented the former British colony for the past two years.

Hong Kong coach Chan Chi-Choi, who coaches Hariyanto at Hong Kong's elite sports institute, was beaming with joy after watching Hariyanto torment Ji into defeat.

"We knew we had a chance before the match," Chan said. "It was always going to be tough but we have seen that Ji does not play as well when he has got pressure.

"He is the Olympic Champion and people expect him to win. But he doesn't like that pressure.

Wwe knew that if we could win a game against him he would start to get nervous," said Chan, who described the result as the "greatest win in the history of Hong Kong men's singles history."

Hariyanto had got off to a flying start against Ji, racing into a 5-0 lead in the first game. But Ji, looking uncharacteristically sluggish around the court, slowly pulled himself back into the game before finally winning the first 15-12.

But encouraged by the closeness of the first game, Hariyanto remained cool in the second and was soon 6-1 up. He maintained that buffer and held on to win 15-11.

In the third Ji's nerve collapsed as Hariyanto chased every shot and forced his opponent to move around the court. Suddenly a string of errors crept into Ji's game and Hariyanto gleefully punished the Chinese star, AFP said.

He wrapped up a stunning victory with a run of six straight points as Ji capitulated meekly.

Hariyanto will play seventh-seeded Indonesian Marleve Mainaky in the third round. Mainaky defeated Thailand's Boonsak Polsana 15-8, 10-15, 15-11 to advance into Thursday's matches.

Other men's and women's singles second round matches were still underway here Wednesday.