Buttner was a loan target for the Istanbul giants.
"United first wanted to get a replacement," he told Voetbalzone.nl. "Because it took so long, United did not let me leave.
"David Moyes saw me being too important to let go. But if I were to be loaned, I was going to Besiktas. People are mistaken about the Turkish league. Besiktas are one of the biggest clubs in Turkey.
"On Twitter I received reports that the Turkish fans already were waiting for me at the airport, which was super nice.
"But now I've heard that I'm going to play a lot, it's up to me to convince United."
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