During a three week session at the Olympic Training Centre in Colorado Springs last January - what Michael Phelps calls "the pivotal moment" of his impossible run - he was beaten every day by guys who had no right beating him.
"It's like I was swimming with a piano on my back. I just don't like to lose; not in swimming, not in Monopoly, ever."
What bugged him more than anything was losing to the guys who loafed half the practice, then suddenly smoked him in the final set.
"We call someone like that a Sammy Save-up and I kind of lost it on a few people."
The problem, as far as Phelps could tell, was that he was seemingly regressing instead of progressing.
Then he went to Bejing. And we all watched it. For a week, there was no ray of light more blinding, no moving object more certain of its destination.
Micheal Phelps gave it everything he had, 100% of the time. Every practice was the Olympics, every interval was the 100m fly finals.
He won eight Olympic gold medals.