Bayer were beaten by Wolfsburg for the young midfielder when he was leaving Schalke five years ago.
"I was sitting at the negotiating table. I have no regrets nor am I annoyed. We cannot bring every player here for whom we care about. Ozil was just too expensive in our view," recalled Voller in BILD.
"I said at the time: people, €5.5 million for an 18-year-old boy who is already having trouble with his coach?
"It's one of those things..."
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