You must not have been exposed to American culture in the 1990s.
American sports culture does not travel like movies and music. Though basketball is a lot more popular around the world than baseball, grid-iron or ice hockey, it doesn't get the same coverage as professional golf or tennis.
I guess I heard the name. Turns out he was that guy in the Bugs Bunny movie I never saw it, and had those Nike shoes named after him.
I was just googling American athletes and - this is really going to freak you out (that i was unaware) - that actor and killer OJ Simpson - he used to be a grid-iron player!
But I'm guessing that there are Americans who have no idea who Pelé is. Or even David Beckham?