In only his first seventeen professional fights, Michael Spinks captured a world title and had beaten three hall of famers in Eddie Gregory, Marvin Johnson and Yaqui Lopez. He also had the Olympic gold medal from the amateurs. Hell even if he had retired at only 17-0 he might have still made the hall of fame.
True, fortunately he did not retire and got his most important victory in the light heavyweight, the one against Qawi. For me he is in the top 5 best light heavyweights of all time, Charles, Tunney, Moore, Foster and Spinks.
The guy was not only a great fighter but was hard as a rock. Correct me if I'm wrong but wasn't it till his fight with Tyson that he suffered the 1st knockdown of his pro career? And he was in with some bangers. I don't remember him even being dazed against those guys.