Duran Hagler Leonard Hearns Duran is one of if not the greatest lightweight of all time this must place him top. As for the other positions it's a matter of personal choice, I personally thought Hagler edged out Leonard so that why I place him second.
All-time standings? Duran probably gets the top spot. He was the greatest fighter of the 70s (along with Monzon) and arguably #1 all-time at 135. He then went on to win world titles at 3 more divisions, including a win over a prime Ray Leonard. Leonard gets 2nd, then Hagler, then Hearns.
#7 Duran #13 Sugar Ray Leonard #34 Marvin Hagler #38 Thomas Hearns I we are talking all time pound for pound.
That list gets my vote too. Hearns at 4th seems harsh but losing (arguably) prime for prime to SRL and Hagler in the 2 biggest fights of his career really hurts him IMHO.
Duran Leonard Hagler Hearns A fighter of Hearns' quality being widely regarded as the weakest of the top 4 really speaks volumes of how strong that era was.