Uh, this is ah-mazingly '70s.
Check out spaceship-flying, superhero-champion Muhammad Ali. I'd ask how I could have gone without knowing this existed, but I wasn't born yet.
The cartoon originally aired on NBC in 1977. Behold:
As you might recall, Ali passed away on Friday, June 3, and is largely regarded as the "The Greatest." So there's no arguing the title of the cartoon, I Am The Greatest: The Adventures of Muhammad Ali.