Teaching shire horse colt to fetch 2

Background: Colt tries to nip me to get scritches all the time. Horse wants something from me? Perfect opportunity to teach something else. I'll bring him to fetch the ball and bring it to get want he wants.
Maybe I'll comment the rest of these, or do it in english. Last time I was rewarding picking up the ball. This time Im rewarding holding the ball. It is hard for him since he instincly opens his maw when the scritching is good. But you'll see he's gets it in the end and fights his own reflexes.
He knows I'm doing the scritching and not the ball, notice how he turns to "nip" me as usual to ask but then changes his mind and goes for the ball. He known what Im asking in exchange and it has to do with that ball.
Keep in mind, this is a very young mind and this progress is real time. Everything done with that ball is in the videos.