Sport: Boxing
Career: 1960-1981
Cockiest Quote: "I'm not the greatest, I'm the double greatest. Not only do I knock 'em out, I pick the round."

Say what you want about all the shit he talked, Ali backed it up. No one gave him a chance when he went up against Sonny Liston as a young up-and-comer out of Louisville. He told everyone they would eat their words and when he beat Liston, Muhammad made sure to let people know. He predicted victories by the round and beat many opponents before they stepped in the ring by talking all kinds of smack. His poems should be kept in the Library of Congress (with our tweets), they're national treasures. Ali bomaye! Ali bomaye!