Monzon, with those long arms and masterful use of range, out-generals Jake, and guts it out when he has to ala Briscoe II. The jab would be working overtime for Monzon, and he would frustrate and outbox LaMotta to win a unanimous 15 round decision..10 to 5 in rounds. Jake would land some bruising artillery of his own in the trenches but it wouldn't be enough to avoid losing to Carlos. Monzon would get Jake's respect with the judicial use of some effective right hands.
LaMotta wouldn't be able to reach Monzon, all the while being jabbed and grabbed repeatedly. The Bull lands some good shots, but has trouble mustering any kind of consistent offense as he comes up on the wrong end of a UD.
Keep in mind that I say things to get a debate going, of course la motta wouldn't get KO'D but I've got to have a message attached to get the juices going right?