Usain Bolt injures left hamstring at world championships in London.

LONDON — Usain Bolt failed to make it to the finishing line in his last race.

The Jamaican great crumpled on the track with a left leg injury as he was chasing gold in the 4x100-meter relay at the world championships.

Instead, Britain upset the United States to take gold in 37.47 seconds. The Americans were .05 seconds behind. Japan took bronze in 38.04.

Jaylen Bacon, a junior at Arkansas State University, ran the third leg for Team USA.

Jamaican team doctor Kevin Jones said Bolt had a cramp in his left hamstring.

“A lot of the pain is from disappointment from losing the race,” Jones said. “The last three weeks have been hard for him, you know. We hope for the best for him.”

Tori Bowie became the first double gold medalist at the world championships, anchoring the U.S. team to the 4x100-meter relay title ahead of Britain and Jamaica.

At the same time, Allyson Felix, running the second leg on the winning team, earned a record 15th medal at the world championships in a career going back to 2005.

Bowie, who won the 100 meters this week, ran a strong anchor leg, leaving behind the opposition to finish in 41.82 seconds.

Britain took silver in 42.12 and two-time defending champion Jamaica earned bronze in 42.19.

Muktar Edris of Ethiopia broke the hold of Mo Farah on long-distance running, outkicking the Briton over the final 200 meters to win the 5,000 meters.

In a tactical race, Farah could not respond to a challenge for the first time in six years, turning his farewell race on the track at a major championship into a disappointment.

Edris won in 13 minutes, 33.79 seconds, .43 seconds ahead of Farah in second. Farah was going for his fifth consecutive global long-distance double.

Paul Chelimo of the United States took bronze.

Kevin Mayer is the new “world’s greatest athlete.”

The Frenchman produced a dominant performance over two days and 10 events in the decathlon, ending with a celebratory 1,500 meters at the world championships.

With two-time Olympic and world champion Ashton Eaton now retired, the event was wide open. Mayer won with 8,768 points. Rico Freimuth took silver with 8,564 points, while German teammate Kai Kazmirek was third with 8,488.