George Chuvalo vs. Oliver McCall
Who had the better chin?
Chuvalo is usually credited for having a chin literally cast out of steal ... but later on he admitted that he really didn't take the all the shots that people think he did and was able to block and deflect a lot of them away from vulnerable areas
Its the same with McCall ... he was never knocked out or even knocked down during a bout like Chuvalo and faced many dangerous punchers ... was also a regular sparring partner for prime Tyson and was reported to have never fallen
I don't think he was ever even stunned in a fight