Pacquiao was heavily favored to win , as many fans and critics believed the 39 - year - old Mosley was past his prime .
Shane Mosley stated that if he lost badly to Pacquiao he may retire .
Pacquiao was heavily favored to win , as many fans and critics believed the 39 - year - old Shane Mosley was past Shane Mosley 's prime .
Shane Mosley stated that if he lost badly to Pacquiao he may retire .