Personally i think in terms of technique and ring IQ, this was mayweather at his best. His defense awareness were insane. How does he do against these mw champs? Jake Lamotta Stanley ketchel Danny Jacobs Carlos Monzon Sergio Martinez 12 rounds no 3 knockdown rule 16 oz gloves.
I believe this was fought at a catch weight under the 160 limit, is this hypothetical also under that ruleset? Not sure the other guys could cut down nor do I think he would be as effective at 160, Off the top of my head I would pick him over Sergio
I don't think a catchweight is fair. Nor would any of these men (Other than possibly Martinez) be able to make 155. I think Mayweather likely loses to all of them at middleweight. I also think Mayweather loses to the more seasoned (and likely roided) version of Canelo from the second GGG fight. Monzon and Ketchel would kick the living crap out of him. I don't think too much of Jacobs, but, he is too big for Mayweather. LaMotta would maul him, and Martinez would outwork him.
I think it was 152Ibs. Though Ketchell fought at lower than that. Ketchell fought at Welterweight pretty close to his prime.
I think Ketchell would overpower Mayweather in a longer fight, but over 12, I'm not sure. Ketchell was a unorthadox, but seems to have been good at getting the big shots home, and as good as Mayweather's defence was, I don't think Ketchell would need to land a lot for it to really take effect. I certainly think he was a hell of a lot more powerfull than Canelo.