They had a series of 3 swimming races, quite awesome. Shaq has great humility and that makes him the funniest dude in professional sports.
First Race:
Shaq goes 25 meters, Phelps goes 50, Shaq Wins
Second Race:
A 4 person rally with Shaq as the anchor swimmer for 3 olympic swimmers, Phelps races the whole thing himself, Phelps win.
Third Race:
Shaq goes 50 meters, Phelps goes 75, Phelps wins.
Shaq wearing a pink swim cap with a flower on it was the highlight. Damn that dude is cool.