1.sugar ray robinson
Alexeyev was a 2 time gold medal winner, and 9 time world champion, and set over 80 world records.
Karelin was a 3 time gold medalist and 9 time world champion, but in 13 years, not only was he undefeated, but DID NOT HAVE A SINGLE POINT scored against him.
It is hard to comprehend this level of dominance on an INTERNATIONAL level in sports that are practiced at such a high level in so many countries.
Sugar Ray? What can I say...200 fights, 173 wins, 106 KO's, this was in an era which fighters were not protected like today, the best fought the best all the time...Sugar Ray WAS boxing...