Edwin van der Sar has written an open letter to Manchester United fans asking them to take care of Donny van de Beek.
Van de Beek has joined United from Ajax on a five-year deal for a total fee believed to be £40m. The Ajax academy graduate made 175 appearances for the Eredivisie champions, scoring 41 goals.
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Ajax's CEO and former United goalkeeper Van der Sar has written to the Premier League club's supporters to look after the 23-year-old who showed "what Ajax stand for".
"Dear Manchester United fans, I hope you’re doing well," Van der Sar wrote in the Manchester Evening News.
"It seems our paths have crossed again. One of ours is joining you this season. And like so many players before him, he’s been with us since he was just a little boy.
"Shortly after his debut, he became one of our best. Especially the last couple of years were amazing. From the Europa League final (no hard feelings) to our Champions League run and winning the Dutch championship.

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"The team he was part of showed the world who we are and what Ajax stand for. Like you, we pride ourselves on being one of the best at developing talent and giving young players a shot at the highest level. You could say your new star is the embodiment of that pride.
"That’s one of the many reasons we don’t like to see him leave, but we understand it’s time for him to move on. To dream on. And where better to do so than in your theatre. Trust me, I know.
Please take good care of Donny, and help him dream. Enjoy the future.
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