It's not just the four gold medals. Or the enduring emotion of a partisan Parisian crowd. It's also because Leon Marchand managed to achieve something almost everyone thought impossible, and that he will be remembered as the defining figure of the 2024 Olympics.

Victory in the 200-meter butterfly then 200-meter breaststroke on the same Wednesday evening was a feat even his coach, Bob Bowman, thought beyond the limits.

"My coach didn't really want me to do that because it was impossible to do and had never been done before," Marchand told DW. "It was really big chance for me and I was really excited to do it, but I didn't know if it was possible."

It was a surprise even to the most decorated Olympian of all time, Michael Phelps, who was also coached by Bowman. Phelps described it as "probably the greatest double I've ever seen in the history of the sport."

Marchand's prowess in the........

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