I personally have never rated Chavez until watching him recently and if anything, I think some of his earlier work gets overlooked (because I have never personally seen it mentioned).

Duran fought with far more ferocity than Chavez, who (pre 90's) IMO was not an emotional fighter at all. Was far more cold faced/ calculated.

I would agree that across the span of his career, Duran showed he was a better boxer and more variation but round for round, looking at one fight at a time, I think he wasn't that dynamic. He either box/punched or savaged. Of course, I'm not saying that he didn't do this well.

What I'm saying is that at lightweight, he was more prone to slip jabs, catch jabs (leaving himself open to left-hooks), get low/ get inside and attack in straight lines. He learned to circle and jab more himself towards the late 70's but I think that against Chavez, he would be Mr. Macho kill, kill, kill and Chavez would have the opportunity to be smart. Use some aggressive lateral movement to open up and kill the body a little. Probably taking the middle rounds. Later on you would probably have to favour Duran (as a 15 round fighter) but who knows?