BoxRec

15 Rounds Super Welterweight Bout

The Bodysnatcher would tear Mattioli down with good jabs and countered his attack with great body punches before he stops Mattioli in 8 rounds on a cut eye or knocking him out with either a right hand or left hook. What do you guys think and who do you got?

X2.

Loved me some Rocky but McCallum would have been a nightmare for him. McCallum would have had a five-inch height advantage and seven-inch reach advantage against a guy who needed to get close to be effective. McCallum would have held him at bay all night with his jab and painted his face as he came in. Mike would have gotten a TKO by cuts anywhere from rounds 8-10

Definitely not the ideal choice opponent for Mattioli. He was a short scrappy "Jr Mw" brawler with decent skills and power.
Basically lower b grade material. McCallum was Elite level, at Least for the most part.

This would basically be along the lines of Hearns-Cuevas and Nunn-Roldan. Paul Williams-Andy Kolle comes to mind as well.

McCallum could literally just remain in safety first cruise control and Tko Mattioli in 7 rounds.
Or go for the knockout, and get it in the 3rd or 4th round.