In small gloves, Jones destroys Willard's face to the point that the fight is stopped. In modern gloves, Jones still probably stops him some at some point. The way they went 30 rounds or more in Willard's day was that they didn't fight for most of the round, did a lot of holding and wrestling. Willard isn't going past 10 rounds against any decent modern HW puncher in 5 ounce gloves.
Can you imagine Roy punching someone in the face in 5 ounce gloves for - forget 45 rounds - say, 25 rounds? It wouldn't happen because it wouldn't last that long - there would be no face left well before 20 rounds.
I'm a little surprised at this thread. It's not as if Willard was mot whipped cleanly by several guys of Jones dimensions.
Roy would win easily, prime Roy won't get tired outboxing Willard at his pedestrian pace and will find it very easy to outbox him. This is a possibility, Roy unlikely goes for the kill, at least the older Roy that fought Ruiz probably wouldn't. But Roy would be 1 of the best punchers Willard ever faced.
I'm not predicting a Willard win but this is a stupid claim. Willard fought Dempsey, Moran, Johnson, and Firpo.