Caeleb Dressel won his first solo Olympic medal after finishing first in the men's 100m freestyle final on Wednesday, setting an Olympic record to do so.
Dressel now has four Olympic gold medals.
Australia's Kyle Chalmers and the ROC's Kliment Kolesnikov earned the silver and bronze medals.
Dressel's time of 47.02 was enough to both break the Olympic record for the event and hold off Chalmers, who finished with a time of 47.08.
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An emotional Dressel cried during the post-race interview: “I don’t know if it’s set in yet. Right now, I’m just kind of hurting. It’s a really tough year, it’s really hard, so to have the results show up, it really came together, so I’m happy.”
Dressel also has two golds from the Rio Olympic Games. He swam in the 4x100m freestyle final alongside swimming legend Michael Phelps, and the heats for the 4x100m medley relay.