JMM, Toney, Evander, Mayweather, Gatti, Antonio, Glen Johnson, Chris Byrd, Vargas, Hopkins etc.. there's so many.
Jean Pascal deserves a mention. The man traded bombs for 12 rounds with an undefeated Carl Froch, fought against top contenders with severe injuries many times, never backed down from anyone, ... Pascal is one hell of a warrior, physically and mentally.
Rios is a good recent example. It's pretty much all he is. Lots of sensible suggestions in this thread thus far though. I'm sure MVC, Boxing Master and various other morons will steam in soon with some nonsense to derail all this logic.
Carl Thompson Steve Collins Toney Holyfield Fury Arthur Abraham Froch's McClellan Pac Marquez Marg Katsidis
Danny Williams when he wanted to be.dislocated his shoulder twice in a fight,come back and won with one arm,got pasted by tyson come back and won,got annihilated by vk but kept on coming