One of the champions is unlikely to lap up adoration or show an overwhelming emotion in the pool. The other is all strut. 

Both styles were on display Wednesday night at La Defense Arena in Nanterre, France, where Frenchman Leon Marchand and American Katie Ledecky added to their growing medal collections.

Marchand, 22, became the first swimmer in 48 years to win two individual gold medals on the same day. Marchand, who had already won a gold, his first Olympic medal, on Sunday in the 400-m individual medley, started off his night by catching Hungarian Kristof Milak with a finishing kick in the 200-m butterfly that sent the capacity crowd of 17,000 into a delirium that caused at least one person in the arena—OK, me—to cover his ears. It was the loudest indoor sports event I’ve ever been to, and I’ll never forget it.

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“I wasn’t ignoring it,” said Marchand of the screams. “That's why I was able to win that race. [I] really used that energy from the crowd.” 

He walked out of the pool, chest out, arms akimbo. He couldn’t celebrate too much: Marchand, who attends Arizona State University and trains with Micheal Phelps’ coach, Bob Bowman, in the United States, left his 200-m butterfly victory ceremony early to prepare for his next race of the evening, the 200-m breastroke.

“I was able to enjoy it, without losing too much energy,” Marchand said.

France's Leon Marchand competes in the men's 200-m breaststroke final on July 31, 2024.Quinn Rooney–Getty Images

When, less than an hour later, Katie Ledecky slapped the water in delight after setting a new Olympic record in the 1,500-m freestyle, her signature race, the gesture may well have been the equivalent of spiking the football, pointing at an opponent, and doing a backflip in the end zone.  

“I was just happy with the time and happy with how it felt,” said the typically mild-mannered American superstar on Wednesday. “I don’t mean to celebrate that much,” she said, unnecessarily. 

Slap away, Katie. Someone with eight swimming gold medals deserves to strut a little bit. 

She’s now the first female swimmer to win Olympic titles in four different Games. With a career total of 12 Olympics medals, she’s tied with three other Americans—Dara Torres, Natalie Coughlin, and Jenny Thompson—for the most ever by a female swimmer. Today she also reiterated her plans to compete in Los Angeles four years from now. She’s still only 27. Torres won Olympic silver medals at 41.

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Ledecky’s winning the 1,500-m freestyle is as close as a sure thing you’ll see in these Olympics: She held the 19 fastest times in the world in that race coming into the night and won the event in Tokyo when it made its Olympic debut. Still, she fought doubts coming into Wednesday. With her first three Paris Olympic swims—the prelims and finals of the 400-m freestyle, where Ledecky won bronze on Saturday night, and the prelims for the 1,500—“each one of them felt faster than the time,” she said. 

She couldn’t help but wonder if something was off.

Once the race began, however, she locked into her process, treating each 50-m interval as its own race. That’s how she operates in her training group, which includes American Olympians Bobby Finke and Kieran Smith, in Florida. “We do a lot of 50s in practice, just holding time, holding stroke count,” said Ledecky. “That's kind of the energy I want to channel into this race. Just getting locked into my 50 and holding.” She says on some training days, her group will do 60 or 70 50-m sprints in the water. 

That labor has paid off. After her 400-m freestyle race, Ledecky got emotional talking about Finke and Smith. In Tokyo, Ledecky said the names of her grandmothers in her mind to push her through the 1,500 m. “Today I kind of settled on the boys’ names, the boys at Florida that I train with every day,” she said. “I was just kind of repeating their names in my head. Just thinking of all the practices that we've done and all the confidence I get from training, from being next to them and racing them.” 

That feeling, by the way, is mutual. “Honestly, she’s elevated my career so much, by how much I learn from her,” said Finke, who won gold in Tokyo, in an interview before the Games. “She’s definitely helped me a ton when it comes to navigating the sport and handling everything.”

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Ledecky’s job completed and victory ceremony concluded—it was the first time the U.S. national anthem had been played in La Defense Arena since Sunday—Marchand walked out to the starting block to roars for the 200-m breaststroke, less than two hours after his butterfly win. Defending 200-m breaststroke gold medalist Zac Stubblety-Cook of Australia called the walkout his favorite part of the race. “Him having that moment, soaking up that moment, that was awesome for the sport of swimming,” said Stubblety-Cook, who won silver behind Marchand. 

Marchand led wire to wire in the breaststroke: each time his head lifted out of the water, the fans shouted encouragement, in unison. “Every time I took a breath, I could hear a huge noise,” Marchand says.  

After touching the wall, he lifted himself out of the pool, pumped his fist, and waved to the adoring home crowd, like royalty.

To cap off a memorable night in Nanterre, China's Pan Zhanle topped his own world record in the 100-m freestyle, finishing in a best-ever 46.40 seconds. Zhanle, it’s worth pointing out, is not one of the Chinese swimmers who tested positive for a banned substance in 2021. 

Ledecky will swim in the 4x200-m freestyle relay final on Thursday, before turning her attention to the 800-m free prelims on Friday. The final for that event is set for Saturday. Marchand has the 200-m individual medley final on Friday.

More slapping and strutting, perhaps, to come. 

But it won’t be better than Wednesday, when Ledecky and Marchand owned Nanterre, and set new standards for their sport, together. 

— with reporting by Alice Park

Correction, Aug. 1

The original version of this story misspelled Leon Marchand's name in one reference. It's Marchand, not Marchard.