Originally Posted by OLD FOGEY
Yes. He was defeated as an amateur. No one ever denied that. He was not defeated as a professional.
But it depends what is meant by professional, I say if you are paid to partisipate in a bout, you are a pro fighter. And if as Janitor says you cannot have a tainted '0', you are either beaten or unbeaten, then I consider that Marciano loss 'at least' one pro fight.