Former Monaco and Borussia Dortmund star retires

Koller was forced to retire due to injury problem. The former Borussia Dortmund, Sparta Prague, Lokeren, Anderlecht, Monaco and Nurnberg star spent last season with Cannes.

He told his personal website: “Stopping my career was unexpectedly easy. I was prepared for a long time. I look forward to what lies ahead in the near future.”