Well, in reality it's probably some SAS/Special Forces kinda guy, but if we're sticking to boxing & as only one person mentioned Gatti, I'm guessing it's Anglo-Saxons/Celts, so that rules out Gatti or Chuvalo, I will have to go for Wayne McCullough. Although I give an honourable mention to Freddie Roach, who in his fighting days was a seriously tough bastard who took some major punishment, look up his old fight footage if you haven't caught it.