3 fighters came to my mind: Julio Cesar Chavez ( A case could be made of him failing against Sweetpea) Roberto Duran (A case could be made of him failing against Leonard) Leonard ( Not much of a ring cuttter, but when he did it against hearns 1 it worked) who do u got? I know I am missing many more
Duran was excellent at lightweight, but after he moved up he was no where as good cutting off the ring.