The 20-year-old, who made just seven substitute appearances in two years at United, reveals in a documentary screened in France: "It was a very very difficult moment for me because I was in love with Manchester and I was a Mancunian.
"And when I arrived I couldn't believe my eyes. There was Ferguson - I was loving it.
"There was no one left to play in midfield. And I was training and I was beginning to get better bit by bit and the coach never stopped telling me 'you're this far, you're this far'.
"And I didn't understand. This far away from what? Playing? From having some playing time? From getting on the field. Or what?
"And there was Rafael in midfield and I was disgusted. I was disgusted and I didn't get on either. I'd lost that thing, that relation that I had with the coach. I was really disappointed, really disappointed.
"I was pushed. My eyes were opened. I'd made this decision to sign with Juventus. There was nothing to regret."
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