How many losses should Mayweather have on his record?

[Master]

Which other "greats" started their careers at a lower weight than Mayweather and had sucess at middleweight?

Duran, Armstrong. Other guys like Gavilan and Napoles started in lower weight divisions than Mayweather started and although they weren't successful against the middleweight champ at least they had the balls to challenge themselves.

Sugar Ray Leonard must be added to the list.