Marciano would lose every round up until the 7th and he ends the fight with the first TRUE solid shot that lands which would be before the 15th rnd!
The Marciano of 1955/56 still had a couple good fights left in him. I believe he would have been super-motivated going for 50-0 against a younger heavyweight of the next generation and would have done what Ingo did in 1959.
I'll throw another wrinkle out there just for the sport of it. There is no guarantee of course that Patterson would have been the chosen one for the magical 50-0. For one, he was still a light heavy at the end of the '55 ratings and just broached the division in early '56. Rocky last fought in September I believe and negotiations would have already started before the end of '55. But the top guys - I think - when Marciano retired in April of '56 would have been Bob Baker, Hurricane Jackson, Nino Valdez, Johnny Holman and probably Patterson just squeezing in there. I left out Moore because Rocky had just beaten him. Looking at it from Rocky's canny manager Al Weill's perspective, and wanting Rocky to go out with a bang, I would have stayed away from the speedy Patterson, the big guys like Valdez, Baker and Holman and gone for Hurricane Jackson. The perfect opponent. He had just nicked a highly controversial decision over Baker in early '56 (I think), he was small and wouldn't duck if his life depended on it. Ergo, the perfect opponent to see off Rocky. Again, just throwing a different angle on this.
Prime vs prime, I go with Marciano, Patterson had fast hands but average foot speed. And a very suspect chin. One has to think in a 15rd fight Marciano would catch him.
I don't think that the fight was likely to happen in 1956, for reasons that I can expand upon if necessary. Cant see it happening until 1957, or perhaps even later. Marciano was seriously looking for a big money fight in 1956, and he retired because he didn’t see anything worth taking. Patterson was barely being talked about! I think that he could have been on very good form, and I think that he would have been way too much for Patterson.
Patterson's last fight would have been a split decision over Tommy "Hurricane" Jackson. (no A. Moore fight). Rocky bombs out Young Floyd in 10 rounds.
Prime vs. prime, Rock by KO. If he'd come out of retirement to fight Floyd, Floyd wins it. Watch videos of Rocky not long after retirement...he gained a lot of weight and he'd have to have really whipped himself into great shape if he'd wanted to be competitive coming out of retirement.
Marciano gets off the canvas to knock out Floyd Patterson in a blazing fight. Patterson would have been ahead on the cards at the end.
Rocky by KO. If Patterson went down easily vs Johansson he'd be an even easier target for Marciano. Of course it would depend on Marciano's condition...did he blow up and get fat between his last fight and this one? How much pasta did he eat in the 1 1/2 years between bouts, and did he keep training. Ali supposedly "lost his legs" in his 3 1/2 yrs away from the ring, maybe Rocky loses his legs, his gut and his punch. Prime for prime though it's no contest.
Im no expert on that era, but funny enough i read Floyd's autobiography last year. I can never get over how light he was for a HW. Naturally walking around at 175 pounds. I remember reading a book on holiday the year before about Rocky, it said that Marciano quit boxing, not because of injury or age,but because he hated his contracted manager who he felt was ripping him off ( was his name Al Weil or similar). So maybe Marciano did have one more fight in him ? Im guessing he out toughs Floyd. As things stand i always think that 49-0 has a real classy sound to it ? 50-0 somehow sounds too neat , LOL !