Of this grouping I feel that only Monzon may be able to defeat him. But if he did it would be a hard-fought close fight and if they fought a series, I can see them splitting about even. And for good measure, I would favor Hagler over the middleweight version of Ray Robinson.
U'd favor Monzon by a bee's prong. I think he'd outbox Tiger quite nicely and beat Fullmer clearly in a tough fight. I think Giardello would actually be a trifle awkward at times but Haglers reach, jab, versatility and the fact that Joey didn't have much to make him take notice would see Marvin home.
I think Tiger has a good not great chance of winning and Monzon is 50-50- the others do not stand much of a chance at all in my eyes.