Caeleb Dressel got the help he needed and delivered a monumental butterfly leg to power the United States to a gold medal in the men's 4x100m medley relay, breaking the world record.
The U.S. finished in 3:26.78 to unseat a 12-year-old mark set by a United States team that included Michael Phelps and Aaron Peirsol at the 2009 World Championships.
Dressel's leg of 49.03 was the fastest in history. He rounded out his Tokyo Olympics with five gold medals, the most by any athlete other than Phelps since 1988.
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Ryan Murphy (swimming leadoff backstroke), Michael Andrew (breaststroke) and Zach Apple (with the anchor freestyle leg) all produced among the fastest splits of the race to help Dressel reach the historic mark.
The United States extended its streak of Olympic perfection in the men's medley relay. The nation has never failed to win the gold medal at any non-boycotted Olympics.
Great Britain, the prerace favorites due in large part to the untouchable breaststroke ability of Adam Peaty, took silver .73 behind the Americans.
Italy claimed bronze in 3:29.17.