No way would Williams be able to keep Mayweather away... he doesn't put enough behind his punches... I think that Mayweather would either come forward, get on the inside and beat WIlliams up like he did N'Dou another guy who was tall and rangy, but with a lot of power. Or Mayweather would back up, potshot and limit Paul's output... I have a hard time seeing Paul land anything against Mayweather.