Noah Lyles finished second-to-last halfway through the 100m final, but then mounted a remarkable comeback in the 50m to capture a historic gold in Paris.
Lyles only led at the last moment in a thrilling race that saw American Kishane Thompson beat him in a photo finish.
Thompson lost by 0.005 seconds, despite the 23-year-old Jamaican running a time of 9.79 on his Olympic debut in France.
It was a heartbreaking highlight for Thompson, who took the lead after 30 metres and held on to it until the last second.
Lyles, on the other hand, was last in line for the first 40 meters of the race, but then quickly worked his way to the front and took a remarkable victory.
Noah Lyles was not leading at any point until the final stages of a dramatic 100m final on Sunday
The American moved from last to first place over just 60 meters to win the gold medal with a time of 9.79
The American was the slowest out of the blocks and only moved into seventh place halfway through the race.
He eventually finished with a new personal best of 9.79.
His teammate Fred Kerley remained in second place throughout the race, until dropping to bronze in the final few meters.
The race analysis made clear how small the differences were between the fastest men in the world: there was only 0.12 seconds between Lyles and the eighth place Oblique Seville.
Lyles defeated Kishane Thompson in a photo finish, with the Jamaican losing by 0.005 seconds
It was the first time that all eight men ran under 10 seconds in a 100-meter race with a permitted wind speed.
“This is what I wanted, it’s a tough fight, with great opponents,” Lyles said.
‘Everyone was prepared for the fight and I wanted to prove that I was the man among them, the wolf among wolves.
Reigning Olympic champion Lamont Marcell Jacobs of Italy was fifth in 9.85 seconds. Lyles is aiming for more gold in Paris in the 200m and the relay.
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