City invited Karius to join the club after watching him in an under-16 game for Germany against Azerbaijan in 2009.
Karius played for City's under-18 and the under-21 teams but never made a senior appearance during his time in Manchester.
The 26-year-old has spent the last two seasons on loan at Turkish outfit Besiktas, following his poor performance in the 2018 Champions League final. He has since reminisced on his time as a youth player and City's approach.
"I had offers from all sorts of clubs back then , but City went out of their way to help me," he said. "They showed me a concrete plan, how I could make it to the senior game. That fascinated me."
"I said to myself: I'm going to take the challenge and go to England. It felt like half of the Premier League [wanted me]. At that time I only listened to the plans of Manchester City and Stuttgart.
The arrival of investors [in clubs] was only just getting started. Manchester City was a club that relied heavily on its youngsters. Many made the breakthrough, the academy was in a good position - that's why I decided on this club."
City's heavily-invested-in academy complex opened in 2010, while Karius was in Manchester.
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