OSAKA, Japan — A scorching final 50 meters made Tyson Gay the world champion.

OSAKA, Japan — A scorching final 50 meters made Tyson Gay the world champion.

The 100-meter matchup Sunday night between the latest American sprint sensation and co-world record holder Asafa Powell was the most anticipated event of the world track and field championships. Gay made it a one-man show.

Under a full moon on another hot, sticky night at Nagai Stadium — with Japanese Emperor Akihito and Empress Michiko looking on — Gay surged ahead of the Jamaican over the final 40 meters to win in 9.85 seconds. A "panicked" Powell couldn't even manage second place. He was third in 9.96, behind Derrick Atkins' 9.91.

Negativity nearly overwhelmed Gay before the biggest race of his life.

"I was wondering, 'Will people still respect me if I lose?'" he said. "I was wondering if anyone would still love me."

A pep talk from mom cheered him up.

"She talked to me and made me a believer," he said. "That's something I wasn't doing. I had a lot of negative thoughts. I was just real nervous and I was getting frustrated. That's what I did was visualize this victory and turn it around."

His parents and younger brother and sister were among the estimated 40,000 who watched from the stands.

"I wanted him to relax and enjoy the moment," his mother, Daisy Lowe, said. "I'm relieved. I feel so much better now. I get so nervous before races. I am so proud."

Gay and Powell were side-by-side at the starting line, but they never looked at each other. Gay sat behind his blocks, intensely staring straight ahead and talking to himself, while Powell paced.

"I was saying to myself basically that I'm the fastest in the world," Gay said. "I was ordering my steps, running through the race. I was thanking God win or lose before the race even started."

Gay was smiling 10 meters from the finish, knowing he had won. When it was over, he let out "a scream of joy." There was some chest-thumping and more shouts, then he grabbed a U.S. flag, draped it around his shoulders, posed for pictures, and took a victory lap.

Powell was grimacing through the final few meters of another disappointing finish in a major event.

"I just panicked and tightened up," he said. "I made a big mistake."

Powell has run a world record 9.77 seconds three times but has never won a world or Olympic title. In fact, his bronze Sunday was his first medal at either event.

"Next year I will get him," Powell said, "but for now I am very disappointed."

Not everything went well for the Americans. Defending world 400-meter hurdle champion Bershawn Jackson slammed into the final hurdle and staggered home a distant third in his semifinal heat, failing to qualify for the finals.

In an example of how stifling the heat was, American 400 hurdler Derrick Williams collapsed after talking to reporters after his race. He was treated for dehydration and was expected to be fine for Tuesday's semifinals.

Meanwhile, Sweden's Carolina Kluft won an unprecedented third consecutive world heptathlon title with a personal best 7,032 points, breaking the European record held by Russian Nikitina Larisa. Only world record holder Jackie Joyner-Kersee has scored more.

Kluft, just 24, has not lost a heptathlon in five years.

Gay succeeds fellow American Justin Gatlin as world 100 champion, and he will try to supplant Gatlin's 200-meter title later in the meet.

Gatlin is appealing an eight-year ban for testing positive for steroids and testosterone.

"I really felt I had to bring the medal home and try to get that cloud over," Gay said. "I'm really hoping that everyone blocks that out and that whole situation disappears."

His time Sunday night was slightly off his world-leading 9.84, run into a strong headwind at the U.S. championships in June. That means the world record still is shared by Powell and Gatlin, although Gatlin is expected to be stripped of the mark once his drug case is settled.

Retired sprinter Jon Drummond has been working with Gay, trying to improve his notoriously slow start and helping him through the distractions of becoming track's next great sprint star.

Gay probably won the race out of the blocks. He was out relatively quickly, not far behind Powell. He caught the Jamaican at about the halfway point, then turned on his trademark powerhouse kick to run away with the victory.

"I looked at the big screen and was kind of mad at myself because I saw how big my eyes were," Gay said. "I was trying to stay relaxed, but I didn't look relaxed. I was trying to get to the finish line first, and when I got to about 10 meters to go I started to feel the joy."

Gay remains loyal to coach Lance Brauman, who is nearing the end of a one-year prison sentence for embezzlement, theft and mail fraud. The charges stem from Brauman's manipulation of scholarships for his athletes at Barton County Community College in Kansas.

"My coach gets out of jail I think in a couple of days," he said. "I'm still looking forward to working with my coach. I would like to dedicate this race to him."

Brauman called Gay Sunday morning.

Said Gay, "He told me basically that he knows in the morning when he gets up that I'll be world champion."