Marvin Hagler fought as a right hander and a southpaw. His most dangerous move was to switch southpaw and throw a lunging power jab as an evasive fighter faded off the centerline and tried to get a breather. My friend—and briefly coach—Johnny Coiley, who preceded Marvin as the New England Middleweight Champion and served as his sparring partner, told me that Hagler was a slick boxer that had converted to a relentless puncher. This would explain his knack for getting into the boxer's game. He had good shoulders and could wing wild punches while still on balance. This was a means to get his man to the inside or punish him for leaving. Marvin's most consistent skill, demonstrated throughout this brutal fight, was his use of the wing block.
Hearns was the perfect punching machine who fought in almost every weight class. Note the whole body punching mechanics. Tommy's legs seemed off for this fight. Marvin's obvious body attack was a cause. But his trainer said it was due to Tommy letting one of his friends massage his legs the night before the fight. Tommy threw every punch with power. He is so much better than Ali was it is not even funny. His hands are low to defend his thin body, which means he has to use head movement and shoulders to defend the head. He augmented his defense with the wing block and the push off that are so neglected today. If he kept his hands up Hagler would have broken his ribs. Tommy was known for his cannon ball right. But his most effective tactical weapon, that had enough power to KO most fighters, was stepping off with the vertical fist left hook. Tommy's use of cutoff punches and moving with the pivot of a punch were excellent.
Watch this film a few times. These men show more punch variation than our current fighters and were still using some old time methods that are just now being brought back by boxers and MMA fighters, such as shift punching and vertical fist power shots.