50 years ago today, 22-year-old challenger Cassius Clay (Muhammad Ali) battered the heavily favored heavyweight champion Sonny Liston in a bout that shook the boxing world. The fight ignited the career of one of sports’ most charismatic and controversial figures, whose bouts often became social and political events rather than simply sports contests. (Neil Leifer/SI)

GALLERY: Muhammad Ali vs. Sonny Liston I

GALLERY: SI’s 100 Greatest Photos of Muhammad Ali

“Champions aren’t made in gyms.

Champions are made from something

they have deep inside them-a desire, a dream, a vision.

They have to have the skill, and the will.

But the will must be stronger than the skill.” 

- Muhammad Ali

Muhammad Ali Vs. Doug Jones

March 13, 1963