Re: Randall 'Tex' Cobb. The undisputed best chin ever?
Hard to say...
I would say Chuvalo did for the sheer number of huge punchers he faced without going down.
DeJohn, Williams, Frazier, Foreman, Bonavena, Mathis, Quarry, and Patterson were all guys that could really whack, and all failed to deck Chuvalo.