"The Greatest" was brought in to be the special enforcer referee for the historic main event at the first WrestleMania in 1985, which pitted Hulk Hogan and actor Mr. T against Roddy Piper and Paul Orndorff.
Ali stayed outside the ring for the most part while former wrestler Pat Patterson handled the in-ring refereeing duties.
However, Ali did get physically involved on a couple occasions, including early in the match when he jumped into the ring and threw a few punches at Piper as all four competitors were mixing it up.
Ali was more of a supporting player than an integral part of the match, but his mere presence on the show helped establish WrestleMania as a wrestling event that was like no other.
I will count down the Top 10 WrestleMania celebrities every day through April 3.