Bobby Finke charged in the final length once again to win the men's 1500m freestyle and complete an unprecedented sweep of the distance swimming events in Tokyo.
“My coaches have been working really hard with me this past year and all I knew is I had to try and race the others," Finke said. "I was just trying to hold on and get my hand on the wall.”
Finke is the first American to win gold in the event since Michael O'Brien in 1984. Team USA's Connor Jaeger won silver in 2016 behind Italy's Gregorio Paltrinieri, who finished fourth on Saturday.
Mykhailo Romanchuk of Ukraine and Florian Wellbrock of Germany took silver and bronze, respectively.
Finke went 25.7 in the final 50 meters to surge past Wellbrock and Romanchuk to secure his second gold medal of the Olympics.
After coming from out of nowhere to win the inaugural Olympic men's 800m freestyle earlier in the week, Finke stayed firmly among the top three for the entirety of the mile-long swim, then turned on the jets to complete the distance double.
Finke's American teammate, Katie Ledecky, completed the first-ever women's distance double earlier in the week, winning the inaugural women's 1500m freestyle and claiming her third straight victory in the 800.