Disagree. Rocky doesn’t necessarily have to land big on the chin early. He will hit Roy everywhere else, incessantly, it will hurt Roy and eventually set up up a wounded, mobility impaired Jones for a howitzer KO shot. Good night Sweet Prince.
Let me rephrase it then: he won't land enough and/or significant enough to ever slow Roy down. He will just hit air and Roy will land on him at will. After 7 or 8 rounds, Marciano's face will look like a pumpkin. Roy might even go for the KO if he hurts Marciano bad enough.
Rocky will find Roy’s body, arms, forearms, you name it. Roy in his desperation to avoid same won’t have the composure or achoring to land as easily as you suggest. Before Nady clamped down on him, causing him to drop tools, Ruiz almost put Roy down with a few innocuous, clubbing punches in the first round. Roy was close to a very inglorious end. Is Roy beating Ruiz the only basis for success against Marciano? The punch stats for that fight were awfully low as I recall. Against Marciano, Roy isn’t going to enjoy the luxury of an opponent just standing there doing virtually nothing or an opponent compliantly allowing the ref to squelch him. All good WB, can agree to disagree.
And I repeat, Marciano will not be able to hit him where you said, he'll just throw into thin air or barely graze Roy at best. Ruiz posed a different problem alltogether compared to Marciano. Ruiz was 6.2 compared to Roy's 5.11, he had a 80'' reach compared to Roy's 74'', and he weighed 226 lbs, while Roy weighed between 190 and 200 lbs. So Ruiz had an edge in all those departments, Marciano will have the edge in none. Marciano will try his hardest I'm sure, but he simply won't be able to do nothing.
Ruiz posed little problem because he wasn’t allowed to execute a game plan that was supposed to challenge Roy - fighting up close and rough. There was nothing remarkable in Ruiz utilising his height and reach when he clearly wobbled Roy in the first round. What exactly was Roy deftly evading thereafter - the punch output on both sides was extremely low and anytime Ruiz hinted at working in close, Nady rushed into to separate them. It was a joke. A total yawn of a fight after the first round. Even for his missed punches, Marciano’s tireless work rate would make Roy work so much harder in his evasions and be less set to counter. Again, every part of Roy’s legally targeted anatomy is Rocky’s oyster. I’m glad for Roy’s sake that their timelines didn’t converge - and even if they did, Roy wouldn’t be fighting Rocky - he’d be scouting for a soft touch like Ruiz with a protective ref in tow.
Jones was no super skilled fighter…let’s not pretend he was. He relied on his freak athleticism. He wasn’t strong enough to stop the heavier weights his career is plain to see. What makes you think he could bother Marciano enough to keep him off him when the likes of Moore, Charles, Louis, Walcott Layne couldn’t?