Floyd Mayweather against Ricky Hatton would be a tremendously popluar fight with success in the money making department. Although the fight would pan out rather straight forwardly and would be a decisive victory to Floyd. Ricky's brawling tactics have brought him success over the course of his career, but these tactics will not be able to be implemented against the great balance of Floyd, who has the best defense in the world, with the ability of moving out of the toughest places in the ring.
It would be nearly impossible for Hatton to implement the brawling tactics on a fast and ever moving Floyd who would simply fight on the outside for the entirety of the fight. Thus leading to Floyd winning by a unanimous points decision. The only way Floyd could loose against Hatton would be for him to attempt to beat Hatton at his own game in brawling and fighting on the inside which would be a plain disaster, which Floyd would well know.