Caeleb Dressel admitted he was feeling the pressure ahead of claiming his first individual Olympic gold in the men's 100 metres freestyle final at the Tokyo Aquatics Centre.
The 24-year-old won two golds at Rio 2016 and has already stood atop the podium in the Japanese capital, but all three of those successes have come in relay races so this represented a chance to stand out on his own.
He pipped Australia's Kyle Chalmers by just 0.06 seconds in a nail-biting contest to capture gold in an Olympic record time of 47.02secs, with Kliment Kolesnikov of the Russian Olympic Committee third, 0.42s adrift of Dressel.
"It is different," Dressel said. "I didn't want to admit it but now that I did it, I can.
"It's a lot different – you can't rely on anyone else. It's just you and the water, there's no one there to bail you out. It's tough.
"I knew that weight was on my shoulders. I'd won relay medals but never individual, so it was really special. It means a lot."
Dressel's US compatriot Robert Finke prevailed in the inaugural men's 800m freestyle final, rising from fourth with one length of the pool remaining to edge out Italy's Gregorio Paltrinieri by 0.24s. Mykhailo Romanchuk of Ukraine scooped bronze.
China took the gold in the women's 4x200m freestyle relay final as the United States, anchored by Katie Ledecky, collected silver while Australia, with double Tokyo 2020 champion Ariarne Titmus in their ranks, finished third.
