Biggest overachiever in heavyweight history

I would say Ali. He wasnt the most talented heavyweight technically, never threw a bodyshot his entire career. Like Holyfield his will to win and mental toughness and of course his natural speed, made up for everything else

 

Anyone mention Don King, yet? He was a small time ex-con and a black man to boot - no pun intended. Although he would turn his skin colour to his advantage, it can't have been the ideal foot in the door in the early 70s. Yet he went on to become, arguably, the most influential man on the heavyweight scene for the best part of nearly two decades.