Mayweather will have been retired with 1 loss to Pacquaio, we see him on an episode of Intervention on A@E due to his heroin addiction (like father like son but instead of crack its heroin). He will have barely enough money to keep a 3 bedroom house in Michigan.
Pacquaio will retire with a win over Mayweather BUT will blow a lot of his money in an attempt to run for President of the Philippines (he learns a little to late that just because he is popular don't mean he can win). His wife with leave him because he fathers two other kids from other women. Pac ends of moving to the states and takes over Wildcard when Roach retires.