Gretchen Walsh won her first individual long course world title by nearly breaking her own 100m butterfly world record.
Walsh clocked 54.73 seconds at the World Swimming Championships, just off her own record of 54.60 from May 3. She owns the top eight times in history.
She prevailed Monday over Belgian Roos Vanotterdijk (1.11 seconds behind, the second-largest margin in event history) and Australian Alexandria Perkins for the U.S.’ first gold medal on the second day of the eight-day meet in Singapore.
“That swim took a lot of guts, but really so happy with the result,” Walsh said on Peacock. “I was aiming for a 55, so to go 54 was really a surprise and something I’m really proud of.”
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Walsh added her first individual long course title to an already stacked resume: four Olympic medals in Paris (including two relay golds), 11 world records and seven gold medals at the world short course championships last December and nine individual NCAA titles in four years at Virginia.
Walsh made the U.S. team for worlds in four individual events and is a medal contender in all of them. She still has the 50m fly and 50m and 100m frees left, plus possible relay duty.
Walsh’s medal ceremony from 100m butterfly
U.S. swimmer Gretchen Walsh is awarded the gold medal at the 2025 World Aquatics Championships for winning the women’s 100m butterfly world title and hears the National Anthem atop the podium.
Walsh was one of the majority of U.S. swim team members affected to varying degrees by acute gastroenteritis, or a stomach bug, leading into worlds.
“My body has just been fragile, and I think that I’ve needed to give myself grace,” she said, according to World Aquatics.
On the first day of worlds Sunday, she said she was feeling tired but trying to make the best of an annoying situation.
After those comments, she later Sunday swam a 100m fly semifinal, then scratched out of the 4x100m free relay final that took place about an hour later.
“I wanted to be on it so bad, but my body would not let me,” Walsh said.
Gretchen Walsh has never won an individual global title in a long-course pool. She could leave worlds with four of them.
Olympic 100m fly gold medalist Torri Huske, who was also affected by the stomach bug, scratched out of the event before Sunday’s prelims to focus on the 4x100m free.
Also Monday, Canadian Summer McIntosh won the 200m individual medley, 1.89 seconds ahead of American Alex Walsh (Gretchen’s older sister).
Canadian Mary-Sophie Harvey edged 12-year-old Yu Zidi of China for bronze by six hundredths.
Yu is the youngest swimmer in history to compete in a World Championships final, according to Olympic historian Bill Mallon of the OlyMADMen.
McIntosh, who won the 400m free on Sunday, is bidding to become the second swimmer after Michael Phelps to win five individual golds at a single worlds. She still has the 200m fly, 400m IM and 800m free (against world record holder Katie Ledecky).
McIntosh pulls away for 200m IM gold at worlds
Summer McIntosh secured her second gold at the 2025 World Aquatics Championships in Singapore, speeding past the competition to win the women’s 200m IM ahead of Alex Walsh of the U.S. and Canada’s Mary-Sophie Harvey.
China’s Qin Haiyang overtook Olympic gold medalist Nicolo Martinenghi of Italy by 35 hundredths to take the men’s 100m breaststroke.
Qin, who swept the 50m, 100m and 200m breaststrokes at the 2023 Worlds, returned to the podium after placing seventh and tied for 10th individually in Paris.
Frenchman Maxime Grousset took the men’s 50m fly, edging Swiss Noe Ponti 22.48 to 22.51. The 50m fly, 50m backstroke and 50m breast debut at the Olympics in 2028.
Worlds continue all week with preliminary heats at 10 p.m. ET and finals at 7 a.m., live on Peacock.
Tuesday’s finals are slated to feature Ledecky in the 1500m free, a race she has never lost in a major final, top seed Kate Douglass in the 100m breast and a 100m back including all three Olympic medalists: Australian Kaylee McKeown and Americans Regan Smith and Katharine Berkoff.
The World Swimming Championships air live on Peacock from July 26-Aug. 3.
