I should imagine he'd come out on top, maybe losing two in ten fights or something like that. It was a very tough bunch of fighters, but not quite as legendarily tough as is sometimes made out. All I mean by this is that it wouldn't have been out of the question for a Hagler, Monzon or Hopkins to reign, it would just be a fair bit tougher than in their own eras. The slightly bigger of the fighters like Eddie Booker and Lloyd Marshall would probably give Hagler the most hassle, probably Charley Burley after that.
Didn't you make this thread like a week ago??? I think Holman Williams would have a very good chance against Hagler. I'd be tempted to favour him based upon what I know. Marhsall gives him fits too, but I think Hagler might be able to get to him and hurt him late.
Hopkins wouln't have reigned. these fighters could be dirty also in adition to tough + hopkins can reign only in very weak eras.
I'd probably go with your man as having a good chance, even with his being smaller naturally, slightly. Hagler would likely up the relentlessness and make it a dogfight, where he is something special, he might win it then, but it would be good to see i'd think. I reckon he'd beat Cocoa Kid and even Bivins, who i have said is probably my number one of that era's uncrowned champs. Williams would certainly make life difficult, but a prime Hagler might not play totally into his hands. And oh yeah, i wish we had more footage. Or in most cases, any.