He's not slipping, He was just new to the game and fighters were not ready for what he was bringing to the table. They are now and it shows. Every since the Lopez fight, Fighters have figured out how to fight him and that's his dilemma. That's what makes them better than the guys he fought before, Knowledge of how he operates. However, if he is in top form, he can't be counted out of any fight. He is only 35, Mayweather was 36 when he put that masterclass on Canelo. Age, while it might be a fact, it is not an excuse. If he loses, it won't be because of his age but because he fought a better fighter.
@Manfred Don't you remember when he was 'no mas'ing top fighters back to back making them quit. He looked unbeatable at that time. You can't compare that Loma to the one who just fought Ortiz.