TOKYO - The true significance of a race can sometimes be told by who stops to watch. Away from the pool deck in Tokyo, in the mixed zone, it's telling that even the legendary breaststroke swimmer decides to take a look at 11.20am on Monday (July 26).

"I saw that race," Adam Peaty says later. He's just won 100m gold but this is required viewing. This struggle, this freestyle duel. This American piano-playing daughter of a swimmer versus the Australian Nadal-admiring child of a runner. Where after 400 fast, hard, lead-changing, lung-burning metres the difference is a fraction of nothingness.