SEVILLE, Spain — Vladimir Dyatchin of Russia retained his 10-kilometer open-water world crown today and two-time Olympic champion Grant Hackett of Australia failed to qualify for the event at the Olympic Games after being disqualified.

Dyatchin, who won last year's championships at Melbourne, edged David Davies of Britain by 0.30 seconds. The 25-year-old Russian swam the four loops of the Guadalquivir River course in 1 hour, 53 minutes, 21 seconds.

Thomas Lurz of Germany, the 2006 champion, finished 6.2 seconds behind in third. Mark Warkentin of the United States was sixth. The top 10 swimmers qualified for Beijing.

Hackett finished 15th but was disqualified for "interference with other swimmers." Swimming Australia spokesman Ian Hanson said Hackett was disqualified for receiving two yellow flags during the race.

The Australians' appeal of the disqualification was dismissed. Hackett has qualified for the 400- 1,500-meter freestyles and 4x200-meter relay in Beijing.

The open-water event, often called a "wrestling match in water" because of aggressive tactics, is making its debut at the Summer Games.

"There were times when there were bodies everywhere — it was that kind of race," Hackett said. "I'm the first to admit that it was never going to be easy and, with 150 meters to go, another swimmer swam over the top of me and pulled me back and I swam over his legs and that's what I was supposedly disqualified for."

Another gold in the 1,500 would give Hackett an unprecedented third straight.

"I am going to hold my head up and move on and get back and prepare for the pool program," he said.