American Katie Ledecky brushed off criticism to set an Olympic record in the 1,500-meter freestyle heat on Monday just hours after losing to Australia’s Ariarne Titmus in the 400-meter freestyle medal event.

Ledecky won her heat with a time of 15:35.35 as the 1,500-meter freestyle made its Olympic debut at the Tokyo Aquatics Centre. The men’s side has long raced the event, but Tokyo was the first time female competitors participated in the long-distance swim.

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The superstar swimmer held off China’s Wang Jianjiahe and Germany’s Sarah Kohler in the fifth heat of the night. Ledecky holds the world record in the event with a 15:20.48 in 2018.

The finals are set for Wednesday.

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Ledecky was coming off a silver-medal finish in the 400-meter freestyle. She placed behind Titmus with the second-fastest time in history. She trailed by nearly a full body length before wrapping up a 3:56.59 mark. Ledecy finished just a second behind her with a 3:57.36.

Astonishingly, Ledecky also raced in the 200-meter freestyle heat before taking the pool for the 400m and the 1,500m.

In the 200-meter, Ledecky narrowly beat out Canada’s Penny Oleksiak. Ledecky recorded a time of 1:55.28 and Oleksiak had a 1:55.38 mark. Australia’s Madison Wilson finished third.

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Ledecky will race in the 200-meter semifinal on Tuesday.

The Associated Press contributed to this report