Stefan Kießling retired from professional football in 2018. He had been playing for Bayer Leverkusen since 2006, and had made over 300 appearances for the club. He scored 142 goals for Leverkusen, making him the club's all-time leading scorer. He also won the DFB-Pokal with Leverkusen in 2009.
The Remarkable Journey of Stefan Kießling: Unraveling the Tale of a German Football Legend