The Dutchman moved to Werder on-loan for the new season.
"At Manchester United, at that time, I think I was just 16 or 17," he told bundesliga.com.
“But if they needed a player or something, then I think once or twice I trained with them. Then after a while, he remembered my face, so would come across in the gym and would speak to me every once in a while. Yeah, so once or twice I trained with the first team lads.
“Obviously, he's a big leader, on and off the pitch. Every once in a while, because he can speak a bit of Dutch still, he used to play at Ajax also, so off the pitch he used to try to help me and speak to me on stuff I can maybe improve. So, that definitely helped also, he has been a help."