I have watched Ali fight on old films, he was great, but Tyson was so powerful, I mean if Ali could last more than 5 rds with Tyson, I think he would beat him, but I don't think Ali would last that long. Tyson beat people, but I meanhe really crushed them most of the time. Think about how devistating he was in 1985-1990 era, we all said this guy was the best ever.