Leonard by decision or late stoppage. Usually a good bet to go with the bigger, faster, stronger guy. Then the legions here will deride him because he didn't grant an immediate rematch.
Interestingly, the man who shared the ring with both of them, Armando Muniz, said that he felt Napoles was the better fighter of the pair, and that he was "very confident" that Napoles would have beaten Leonard. Personally, I'd take Leonard's natural size and speed advantage as reassuring factors in his favour here. Napoles was an unbelievably smooth boxing machine but Leonard had incredible adaptability and wouldn't mind Napoles bringing the fight to him. Benitez, Duran (II) and Hearns all required very different game plans and qualities to get the job done, and Leonard proved he could find a way to adapt to all kinds of problems. I genuinely believe that a peak Napoles, in terms of all-round talent and virtuosity, has only three, maybe four Welterweight equals or superiors in history - unfortunately for him, I think he's up against one of them here and I'd take Leonard to win a hard-fought decision in a classy fight. Chance of a late cuts stoppage if Napoles has to chase for the knockout and Leonard likewise feels confident that he's softened Napoles up enough to push for one himself.
I consider Napoles as the better boxing technician but in all honesty I think Leonard would have found a way to beat Napoles. Leonard had the size, speed, power, and intelligence to beat Napoles either in a boxing match or a brawl. It also doesn't help that Napoles was prone to getting cut, which Leonard would take advantage of. If Leonard can stop a huge power puncher with boxing skills (Hearns) and a slick defensive technician (Benitez) then surely he'd be capable of stopping a guy like Mantequilla IMO.
This might be my all-time WW dream matchup: '69 Napoles v '81 Leonard I'm really conflicted here as I love Napoles. I have him at no. 3 all-time at WW, one place ahead of Henry Armstrong but one behind Leonard. As much as it pains me to say it, Leonard as the naturally bigger guy and with the speed to trouble anyone, plus excellent power would probably get to Napoles eventually. I think Mantequilla shows all of his legendary slickness but maybe his natural aggression plays against him here. If he was content to box defensively he might be able to find his way to a points win but I don't think he would and Leonard would ultimately get his range and overpower Napoles late to get either a premature stoppage on cuts or a legit one. Maybe.
I just read your comments after I posted mine. Very similar perspective but you're right about Ray's ring IQ - he could bring Napoles into a fight and I think Jose would oblige him. That would probably be his undoing.
I think the peak Napoles was a slightly better fighter than Ray but like others have said I'd lean towards Leonard's big edge in size and speed. I think he'd get hit hard and countered frequently throughout the fight but just keep pushing Napoles back, taking one to land two, taking two to land three and beating Napoles to the punch. He did telegraph a little bit and Napoles was one of the great smooth slip-counter fighters but the I think his problem would be that he didn't close the gap as quite quickly or have the same freakish reflexes as Duran. He tended not to shore up his defence or box on the back foot either when getting hit, despite having the tools and footwork to do do. He was just s bad arse aggressor despite the silky style and always fought on the front foot. I think Leonard would have a harder time if he opted to box rather than be the aggressor. He'd be giving up his natural stalking boxer-puncher approach and advantages of physical superiority to a smaller, slower man who was great at tracking movers and keeping them in range. It'd be showing too much respect imo and would give Napoles a better chance of winning if were able to build up a head of rhythmic steam against a mover who didn't always blend his defence and offence brilliantly. Like I said, Leonard to win close but clear in a superb fights but I think he'd have to cut Jose to stop him, else mark him up and make his eyes swell so badly that his vision is more or less gone, because Napoles had an iron chin.
Napoles would give Leonard hell with his subtle, baiting movement and fantastic offense. But ultimately, I feel Leonards will and physical gifts would allow him to seize the victory. I never actually viewed Napoles as in his prime at Welter (except for Cokes 1), which just goes to show how great a fighter he was, though I think experience was a massive development t of his style.
It would be a fantastic fight, and I see Leonard winning it, not by KO, but decision. Mantequilla makes it difficult for him.
I’ve got to say I’m wavering on this one. I went for Leonard but not positive. It’s a great, great matchup this one.
Napoles, all day every day. Much better fighter. That said, Leonard always found a way to win. But Napoles is much better.