Canadian Summer McIntosh clocked the second-fastest 400m freestyle swim in history on Thursday, touching in 3min 55.37sec to win at the US Open long course meeting in Austin, Texas.
McIntosh, winner of three gold medals at the 2024 Paris Olympics and four world titles in Singapore this year, said she was "pumped up" for her first competition since she began training with new coach Bob Bowman in Austin, and it showed.
"This was my first race back for the season, my first under Bob, so I was pretty pumped up for it," McIntosh told streaming service Peacock.
"That's definitely by far the fastest I’ve gone in-season, so I’m excited at what I can do in the next coming months."
US Open, Day Two Finals (Women): Summer McIntosh Rips US Open Record in 400 Freestyle; No 2 Time in History - https://t.co/NHJWI7WGGj pic.twitter.com/bTU5lKzRHc
— Swimming World (@SwimmingWorld) December 5, 2025
The 19-year-old had been forced to pull out of her scheduled short course World Cup appearances in October because of illness.
But she was dominant on Thursday, swimming under the pace of her world record of 3:54.18 for much of the race. Anna Peplowski was a distant second in 4:10.55 and Emma Weyant third in 4:11.25.
France's Paris Olympics hero Leon Marchand, who also trains with former Michael Phelps mentor Bowman, made a strong start in his first long course meeting since winning two individual world titles in Singapore in July-August.
The four-time Olympic gold medallist tested himself in a new event, winning the 400m freestyle in a personal-best 3:44.70 with rising US star Luka Mijatovic, 16, second in 3:45.30.
"It's awesome," Marchand said. "I've been trying to do the (400m free) since last year. It's such a tough race to build. I'm happy with the time but also the way I did it.
"These guys were tough to beat... the last 100 was really hard for me. My legs were burning, but I'm also doing my PB by three seconds so it's probably worth it."