jack wins hands down much too clever and a better boxer while diego has the heart he doesnt have the right tools for this matchup
Jack would've been hard for pretty much any LW to body effectively, and he'd have out-muscled and tossed around Corrales pretty easily IMO. Corrales has power, but not the skills someone like Williams had to land the clean shots to put him out. Jack had a hell of a chin, as was proven in his bout with Williams, when he took repeated clean shots straight to the dome while half out on the ropes. Never once hit the ground in that vicious assault. Also out-bodied and decisioned a past prime Armstrong from what I understand. I'd think he would put the hurting on Corrales and keep him from doing any effective work in close by keeping him off balance or forcing him to move. He'd stop him at some point.
Jack would bully Coralles around the ring and punish him to stoppage inside of 9 rounds. I don't see Diego hanging in with someone as strong as Jack, with his chin, and his aggressive style.