OSAKA, Japan - Tyson Gay planned to go slower. He just couldn't.

Gay and world record holder Asafa Powell finished second in their heats in the first round of the 100 meters at the track and field world championships early today, both trying to conserve energy for the next rounds.

In the opening heat, Gay was slow out of the blocks and finished behind Nobuharu Asahara of Japan in 10.19 seconds - his slowest time in competition this season.

It was the first time he has been beaten to the finish, yet it still was faster than he planned.

He said his goal was to run 10.30, so beating that mark was a surprise.

"The track would not allow me to do it," he said. "I could not really run slow."

Gay has his eyes on the gold Sunday - and Powell's record of 9.77.

Powell, of Jamaica, cruised after a fast start to cross in 10.34, behind Keston Bledman of Trinidad and Tobago.

Kenyan Luke Kibet won the men's marathon by the biggest margin - 79 seconds - in the history of the championships.

When Kibet hit the tape in 2 hours, 15 minutes, 59 seconds, he just had won the slowest major championship race at low altitude in 51 years, going back to the Melbourne Olympics.

The U.S. squad includes 14 Olympic medalists, 10 reigning world champions, 10 American record holders and 11 who have world-leading marks for the year.

Some of the best of them still are in the early stages of what already are outstanding careers.

Jeremy Wariner, the reigning Olympic and world champion at 400 meters, is 23. Allyson Felix, defending world 200 champion and 2004 Olympic silver medalist, is 21.

Sanya Richards is considered the best female 400-meter runner in the world, but she failed at the U.S. championships to qualify for the event. Instead, she will challenge Felix in the 200 and run in the 1,600-meter relay. Richards is 22.

Associated Press