Name some of the most underappreciated southpaws in boxing history. I'll start off and say Orzubek Nazarov. He reigned as a WBA Lightweight Champion from 1993 to 1998. His short career ended with 26 wins and 1 loss.
Juan Carlos Gomez. The guy was a dominant Cruiserweight that a lot of fighters wanted no part of. I remember reading a story about how James Toney declined an offer to fight him and held out for a fight against Jirov instead. Gomez is severely under appreciated.