LONDON — Usain Bolt was no longer stunning. He was just stunned.

At the end of a career in which he has dominated his sport for a decade, Bolt was beaten in his final 100-meter race by an American almost five years his senior – Justin Gatlin.

Calling it quits at the age of 30 and looking for a golden farewell in his last individual race at the world championships, Bolt lost to a man who produced a comeback not only on Saturday but also through a doping-tainted career.

In a tight finish, Bolt was punished for his slow start and Gatlin fought back to nip everyone at the line in 9.92 seconds. Christian Coleman took silver in 9.94 seconds, while Bolt got bronze in 9.95.

“My start is killing me,” Bolt said. “Normally it gets better during the rounds, but it didn’t come together.”

Also Saturday, Isaiah Harris of Lewiston advanced to the 800-meter semifinals by finishing second in his first-round heat.

Harris, the runner-up at the U.S. championships in June, finished his heat with a time of 1 minute, 45.82 seconds. Fellow Americans Donavan Brazier and Drew Windle also were among the 24 runners who qualified for Sunday’s semifinals.

Gatlin knows what Bolt has meant to the sport, graciously bowing in admiration in front of him – even after beating him. The two men, never really friends, warmly embraced and spoke.

“It’s just so surreal right now,” Gatlin said. “Usain has accomplished so much in our sport and inspired others.”

It was an amazing turnaround for Gatlin, who was the 2004 Olympic champ before Bolt emerged and won an unprecedented three straight 100-meter titles at the Olympics.

The 100 final was overwhelming, and so was the women’s 10,000 as Almaz Ayana tries to turn massive victories into a tradition.

After winning the Olympic title in Rio de Janeiro with a runaway world record, the Ethiopian made sure her margin was even bigger at the worlds – three times as big.

Ayana won in 30 minutes, 16.32 seconds – 46.37 seconds ahead of Ethiopian teammate Tirunesh Dibaba. In track terms, that is more than 300 meters in a 10-kilometer race. Agnes Tirop of Kenya took bronze.

Ayana had been hampered by injury this year and had no official times in the 10,000.

“I have been sick this year and didn’t expect it,” Ayana said. “In fact, this was my first race of 2017.”