TOKYO — Caeleb Dressel had already done everything under the Japanese sun when, a little before noon here on Sunday, shortly after receiving his fourth gold medal of these Olympics, he dove into a Tokyo Aquatics Center pool one final time.
Only three male swimmers had ever won a fifth gold medal at a single Games.
To join the club, Dressel would have to erase a deficit. He took on the third leg of the men’s 4x100 medley relay, an Olympic event the U.S. had never lost, with his team in third place.
And he’d been thinking about the microscopic margins of these moments, the unparalleled stakes tied to hundredths of seconds.