The predictions before the Tyson fight basically answer that question. Tyson was very reasonably the favorite, but people expected it to be a Marciano Charles type affair.
First of all, forget the knee brace. Michael's knee was long healed by then. But he was used to wearing it, and it was merely a precaution. What happened in Tyson-Jinx was simple. History's fastest starting HW Champion in recent times quickly wiped out one of the slowest starting power punchers ever, and that victim went into the ring not warmed up, but utterly cold. Everybody accurately predicted the outcome, and Mike did exactly what he should have done. So, let's assume Michael doesn't want to end on that note, but go out a winner like Braddock aimed to do. The then undefeated Damiani might be the right guy. He had the cachet of being the first amateur to beat Teo Stevenson since the 1971 Pan Am Games. He stopped amateur nemesis Tyrell Biggs faster than Tyson did. He was undefeated until 1991, when a freak light left uppercut shattered his nose in a bout against Mercer which the Italian had been dominating and had clinched the scoring on all three cards. (The red light was flashing for Ray, but he ignored it, and the wily, guileful veteran Holmes made him pay dearly for that a year later.) The slow starting Jinx would definitely have a chance to warm up against Damiani. Then, the gifted Italian cutie would, like Holmes, see things he'd never see before or since, attacks from weird angles, and Francesco, even in Milan, Rome or Rimini, would lose the only decision of his career, and via UD. Michael might go after Ribalta, the promotional hook being that Jose had knocked out brother Leon in one. A HW rematch with Qawi might work, and as with Ribalta, what Qawi did to Leon in 1986, taunting the helplessly weight drained older Spinks brother as Dwight did, might well work as a promotional hook. Revenge!
Mike Tyson exposed him. Spinks's victories over an over confident , old out of shape Holmes, and the rematch, which easily could of went to Larry, a drug/ alcohol addicted Cooney, who was only looking for a payday, and hadn't been serious about boxing since the Holmes loss( Four- five years earlier) And something named Tangstad were not impressive. Spinks avoided much better heavyweights available until he could cash in his chips against Tyson. Tyson did what multiple other heavyweights of the era would've done to Spinks.... Just not as dramatically, and without the financial compensation.. Spinks was smart enough to" take the money and run". Steve Miller Band ......
This assumes that Spinks had anything left in the tank. But who knows. After his own loss to Tyson, I doubt anyone would have thought Holmes had as much left in the tank as he actually did.
If he had no injuries, then until around 35, he could beat Mercer, Morrison, McCall, Page etc but would come unstuck against Lewis and Holyfield. Witherspoon would be 50/50. If Spinks has the injury, he probably beats none of them.
