After almost 20 years as a professional footballer, today marks the end of my active career," the 35-year-old wrote on Instagram. "As a little boy, I had one dream: to become a professional footballer. The fact that I got to live that dream for so many years is something I'll be grateful for every single day of my life.
Football has given me more than I could ever have imagined. It has shaped me, helped me grow, taken me to places I never thought I'd see, and introduced me to people who will be friends for life. The Borussia Mönchengladbach and Alemannia Aachen youth product went on to make 225 Bundesliga and 137 Bundesliga 2 appearances across spells with Aachen, Schalke, Mainz, Bochum, Hamburg and Holstein Kiel.
Eligible to represent both Germany and England at international level, the midfielder opted for the former, winning the first of three senior caps in a friendly against Sweden on 17 November 2010.
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