Tommy would have the ability to both outbox Kelly and end the the fight with one punch. I would bet Hearns in this fight. That being said, Kelly absolutely has the power to KO Hearns and if Hearns let himself get caught, has Hearns often did, he would be out cold. Part of what made Hearns so great to watch was knowing he could spark just about anybody, but that he had that flawed chin and willingness to expose it. He was always on the verge of losing to a good puncher, even if he was winning.