Not sure. Jones was a little green at 160 and still improving and getting more experience, but he was a bigger 160 than Hagler was, under different weigh-in rules.

Jones later on developed a lot of experiences against southpaws, but didn't have much when he was a middleweight.

I'm thinking that Hagler's best game-plan should not be his usual patient boxer-puncher style and maybe he should throw caution to the wind and swarm Roy like he did Tommy.