Usually people get beat by the same man twice.. it's rarely done in boxing. In reality no one has gone undefeated apart from Floyd Mayweather.. Marciano retired premature.. coulda stayed on for another fight with Liston/Patterson/Joe Louis.
:huh Another Louis fight? The version he beat of Louis was already shot enough, no? A rematch becomes incredibly hard to make when you consider Louis retired after the Marciano fight...