Well i agree if Mayweather is retired but in my list Pacquiao no way goes to P4P number 1. Based on Mayweather having more achievements winning titles at more weight classes, beating more quality fighters and i know Pacquiao fans will throw names like Barrera, Morales, Marquez etc. But actually take a look at both Mayweather's and Pacquiao's whole career, and clearly Mayweather has beaten more quality opponents. Plus Mayweather is a better fighter than Pacquiao P4P so thats my reason's.