Who do you think was the best inside fighter of all time? I few that come to mind quickly are Tyson and Toney
tyson was nothing special when he got on the inside. he would often just let his man tie him up without much of a fuss. tyson was dynamite at mid-range.
Duran & Chavez at their peaks could tattoo your body & head repeatedly while slipping & blocking expertly which is the very art of great infighting. Plus, they were made of iron too, so the shots that did get thru usually didnt do **** except make them step it up a gear.
I think Pernell Whitaker is a superb and possibly underrated inside fighter who deserves a mention, but of course the answer here is Roberto Duran. By a mile. I have never seen Henry Armstrong fight on film, so for me it's Duran 100%.