Bruno had decent boxing skills, a hard punch but a shocking chin. Hmmmmm, tough call but I'd say Haye by KO
Until Haye actually does something at heavweight I'll go with Bruno who did at least prove he's world class fighter at the weight. Bruno KO.
Prime Bruno would KO Haye within 5 rounds. He staggered Tyson and had great power, his chin wasn't tremendous but it was his stamina that let him down usually. All of his losses bar Tyson occured later in the fight, Bruno would blast him out early.
This is a myth that Bruno did not have a good chin. Show me the fight where Bruno was KO cold by one punch or hurt by a soft punch? Bruno was never good at covering up and hanging on when he was hurt by a big punch and did have stamina issues in his early days. I am going with Bruno by KO win over Haye rd6.
If Bruno were fighting at his prime now, people would be saying "Haye's not ready to go straight in with Bruno, he should have a warm up against someone Bruno's already beaten, like Wlad or Peter, before he steps up to that".
Bruno had a fragile chin.. (Myth) Frank got up or stood up to Tyson in both title fights.. Frank was more exhausted against Witherspoon and never actually hit the floor.. Smith hurt Bruno with an extensive number of head shots and at the end he was still getting off the floor when he was stopped.. Frank was easily beating Lennox when he was stopped, he was caught against the ropes and stopped on his feet.. Frank was too brave... He was bigger naturally and stronger than Haye.. Frank had a far better jab and better KO power.. Bruno by easy KO... NC....
A prime Bruno would pound Haye into the canvas, we all remember how much trouble he gave Lewis in 94 or 95, going jab for hab with him, and winning with it early on, I see Bruno doing the same to Haye, but this time winning by 4th round knockout.