Updated July 28, 2021 at 11:05 PM ET

TOKYO — U.S. swimmer Bobby Finke had his work cut out for him heading into the last lap of the men's 800 meter freestyle final.

He was in fifth place for most of the 16 lap race.

Then, he surged from behind in the final 50 meter stretch.

"I noticed 10 meters out I was catching up a little bit of ground and that was the only motivation I needed to try and pass and get my hand to the wall first," he said after the race.

The 21-year-old from the University of Florida made up almost a second and a half – which might as well be a lifetime – to blast past the other swimmers and win the race in a thrilling finish.

He beat Italy's Gregorio Paltrinieri by less than a quarter of a second, smiling and pumping his fist as the victory sunk in.

Finke came into the Olympics as a longshot for a medal in the event, which was making its Olympic debut.

He told reporters that before Tokyo, his best time in the 800 meters was about five seconds slower than the time he pulled out to qualify for the final.

And today, "I dropped another second. I had no idea I was going to do that."

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