Pacquiao was @140lbs.when he beat Diaz then Oscar wanted Pacquiao but why cant he fight Pac at 140lbs.?

The fight wasn't a catch weight it was at 147, manny was coming up form 135 so he couldn't fight ODLH at 154 his natural weight, any way Oscar is the one who called Pacman out and wanted the fight at 147. So if any one should be blamed for Oscar being drained its Oscar.