Bruno would brutalize Haye from the outside. First two rounds could be competitive, then Haye hopelessly runs out of gas and gets outclassed.
Like most fans I love Frank Bruno, but we shouldn't kid ourselves that he was very good. He'd always deal impressively against handpicked opponents, but against world class fighters he nearly always lost. Haye would stop him, guaranteed
You're right about Bruno, but Haye hasn't ever faced a single world-class heavyweight himself. We have no idea how Haye would perform as he is carefully handpicking his HW opposition. Bruno would be 10x of anybody Haye has ever faced in the ring so far. A much more complete and better package than the limited cruiserweights Haye has boxed (5"10 Mormeck or glasschin Macca) or the over-the-hill HWs Haye climbed in the ring with (38 year old Barret or 38 year old Ruiz). A prime Bruno would by far be the toughest opponent Haye ever dealt with. Could he win? Sure, he has a chance. But I'd give Bruno 7 wins out of 10 fights, 3 wins for Haye in an upset scenario.
whilst it's true that frank often fell just short (mccall fight being the exception) i don't see haye doing any better with terrible tim and bonecrusher smith who both had their hands full with frank. lets not even get into the prospect of haye v tyson/lewis who frank once again had his moments against. haye is a level below all of these guys.