No-ones mentioned Tyson yet so I'm going to. Undisputed heavyweight champ at 21 (I think) and WBC champion at 20.
Here are some that come to mind: De La Hoya Mosley Ali Hopkins Judah Vargas Leonard Duran Margarito G.Johnson etc
How great would Sanchez have been had he not died at such an early age? He is already an ATG and probably was not even prime before he died yet people here tend to give him so much respect. I am too young to have been watching his fights back when he was alive.
Remember heavyweight James Broad, he beat Bonecrusher Smith in his debut, and went on to face numerous heavyweight champs throughout his career.. Ruddock, Tucker, Duplooy, Witherspoon, he faced almost everyone, and beat some top class names..
Maskaev fought and beat Alex Miroschnichenko in his first fight. I think Miroschnichenko had beaten Lewis in the Ams and was unbeaten in about 30 at the time.
Without checking Boxrec (at work ain't got time) I think he was 25-0 (15) at the time or something like that.
i know Americans are going to ***** about this but.... Joe Calzaghe fought Chris Eubank, Robin Ried and Ritchie Woodhall very early in his career.