Close decision either way. Benitez fought on pretty even terms with Ray Leonard and Carlos Palomino. He'd have an edge in strength and size. He wouldn't have to worry about Floyd's punching power nearly as much as he did with Palomino, Leonard, Duran and Hearns.
Now I haven't seen the Curry/Benitez fight, but when these fantasy matches come off I'm assuming we're talking about the best possible versions of these fighters at the given weight. Seeing as how Benitez was able to fight on pretty even terms with Palomino, Leonard and Duran (as a light middleweight), I think it's safe to say he'd present Floyd Mayweather with a lot of problems at his best, especially considering his style and his comfort level fighting a slower paced fight.
Is this the same Benitez who was very lucky to get a decision win over Bruce Curry (Donald's brother) after being dropped a couple of times? Curry wouldn't have won a round against Mayweather. Benitez won the 147 lb title by a split decision in Puerto Rico, defended it once against journeyman Harold Weston, then was beaten by Leonard. Benitez was a talented fighter to be sure, but lets not get carried away with the myths of that era.
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