Louis KO's Dempsey in 4 Marciano KO's Dempsey in 8 Floyd Patterson can outbox dempsey but I would pick Dempsey Via KO inside 3
Louis vs Dempsey is a pick'em fight. If you look at the first Louis-Godoy fight, Godoy fought in the Dempsey crowding/bobbing style and lost by split decision (lots of journalists thought Godoy deserved the nod). But Dempsey hit much harder than Godoy, so I'd have to favor Dempsey here only slightly. Marciano vs Dempsey would be a barn-burner with Marciano's stamina being the deciding factor. Marciano wins by UD (Dempsey was never KOed in his career, so I can't assume he would get KOed). FLoyd Patterson would box nicely for a few rounds, but Dempsey would eventually land that punch to the chin and stop him.
Flynn is claimed to be the first and only man to KO1 Dempsey in the first round. Marciano been done but always came back to win... Dempsey mentally stronger Tyson... Holyfield would have UD :hey