Pernell Whitaker
You’d be hard pressed to find a better pure boxer than Pernell “Sweet Pea” Whitaker. He tends to be underrated a bit because of his style and lack of devastating punching power.
But Whitaker won six world titles, including unifying the lightweight division, and holds wins over Greg Haugen, Jose Luis Ramirez, Azumah Nelson and Buddy McGirt.
Whitaker was robbed more than once in his career, in his first world title challenge against Ramirez and again in the draw against Julio Cesar Chavez. Whitaker clearly won both fights, and you could also argue that he deserved a win over Oscar De La Hoya as well.