I don't know Pacquaio was 144 when he came into the ring fighting Morales, and Mayweather has yet to come into a fight over at 150 pounds or more. I think it would be easy for either man to fight at a catch weight 140-145 even after Mayweather goes up to 154. However I think he would be too good for Pacquiao to overcome, and in might even be a very ugly beating received by Manny.