Canada’s Summer McIntosh set a new US Open record in the women’s 400-metre freestyle on Thursday night at the Toyota U.S. Open Championships.

McIntosh, a three-time Olympic champion, finished first in 3:55.37.

She was over 15 seconds ahead of her nearest competitor, American Anna Peplowski, who took second in 4:10.55. American Emma Weyant was third in 4:11.25.

American Katie Ledecky set the previous U.S. Open mark of 3:56.81 last April in Fort Lauderdale, Fla.

McIntosh, from Toronto, was just over a second behind her world-record time of 3:54.18 set last June in Victoria.

Competition continues through Saturday.

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