Robinson is considered the GOAT by most boxing historians ahead of Ali. He fought and defeated the best of several divisions. He had speed, power, defense, granite chin, and immense technique. I cannot think of anyone who is better.
It is generally accepted that he is, with Armstrong, Greb, Ali and a few others being in his general class.
Which one? Im gonna go ahead and assume SRL? Nope. His resume : 21 yo Benitez (yeah he was champion but this may as well have been a prospect vs prospect fight). Stick insect weight bully Hearns who had barely any good wins (KOing past prime/fat much smaller Duran is not impressive) Getting beat by the smaller man, a lightweight, in Duran. SRL vs Hagler was not prime for prime, SRL is literally on record saying he cherrypicked him after he looked trash. Someone else do SRR for me.
One of them though I think Charley Burley might have been even better.Burley was avoided by SRR and others for a reason. Both Eddie Futch and Archie Moore said he was the best ever and their opinion are to be respected.