I think if heart alone made a great fighter cast your mind back to this -
Thomas Hearns v Dennis Andries , was a brutal slaughter from start to finish Andries showed true heart.
and another quote this time from Manny Stewart who took Andries to Kronk after the fight with Tommy.( and remember how bad Andries was in the fight )

a member of the press said to Manny . " strange choice taking Andries to Kronk at his age , i mean you cant teach and old dog new tricks "!!!!!

Manny replied " This old dog Dennis does know any tricks " lol classic

and of course Manny made Dennis a champ in Kronk colours.