A world-renowned African-American champion boxer, "a true genius of the ring and champion of the people!"
In 1978, the boxer and Superman are confronted by aliens known as "the Scrubb" who seek to break the will of and destroy humanity. They're challenged to fight the Scrubb's boxing champion, Hun'ya, or have the world be destroyed by their refusal
Faced with that threat, the pair agree to the challenge and train with each other. In addition, they also create a plan that allows Superman to be free to fight the Scrubb's space fleet while Muhammad Ali keeps the galaxy's attention glued to his bout against Hun'ya.
In the ring, Ali beats Hun'ya while Superman successfully defeats the fleet, and so, inspire Hun'ya himself to revolt against his leader and help end the threat against Earth.
The danger to Earth thwarted, Superman and Ali depart amicably with Ali revealing that he has deduced Superman's secret identity but intends to keep it to himself. (All New Collectors' Edition No. 7, 1978).