The reason why Floyd Mayweather Jr. is doing it is he knows he would lose his unbeaten record to Manny Pacquiao.
That only makes sense if he knew Manny would refuse the testing.
“That only makes sense if he knew Manny would refuse the testing.”
That’s easy enough: Manny Pacquiao has said he won’t allow blood to be drawn within a week before the bout. So naturally that’s what Floyd demanded, since he is desperate to avoid the fight.