Ali used Mel Turnbow at least once;for the Foreman fight. Turnbow practically made a carrer of getting knocked out in one or two rounds by rising hevyweights, but he was strong and a very hard puncher, which was what Ali wanted in preparing for Foreman. I think he also sparred with Jimmy Ellis, but not certain.
near the end of Ali's career he used some young future champs as he prepared for Spinks. Michael Dokes and Tony Tubbs were in Deer Lake. Tim Witherspoon also sparred with Ali as did Larry Holmes for a number of years before being top 10 and champion.
A well known sparring partner is Eddie "Bossman" Jones. Jeff Merritt and Roy Williams were also used as sparring partners according to Larry Holmes' book
Light heavyweight Allan Harmon, who was Ali's roomate for a while was a sparring partner early in his career. Others included Cody Jones, Bossman Jones, Mel Turnbow, Rahman Ali, Terry Lee, Larry Holmes...
He used Johnny Hudgins, Rufus Brassel, along with Blue Lewis, for his comeback against Jerry Quarry. George Hill boxed exhibitions with Ali and might have sparred also.
:)
He sparred extensively with Larry Holmes for 'The Rumble in the Jungle'. That excellent movie based around the fight, 'When we were Kings', shows some footage of their sparring. Ali's already doing the rope-a-dope.
Don't forget his famous sparring session with Ingemar Johannson while Johannson was training for the third Patterson fight (I think)! By all accounts, Clay (at the time) outclassed him and Johannson quit because he couldn't hit Clay. It exists on film for those interested at http://www.sweetfights.com
Ingemar wasn't interested in chasing a dancing sparring partner.
He was preparing for a different kind of fight, with somebody coming at him, like Patterson.
YT