 His legal actions in Germany set a precedent for professional sports in Europe, known as the Kolpak ruling, which have had a wide-ranging effect, especially in regards to English county cricket and British professional rugby union.Kolpak played for Tatran Prešov, Dukla Praha and VSŽ Košice before moving to TSV Baden Östringen in the German 2nd Bundesliga in 1997.He played for the club and its successor SG Kronau/Östringen (now Rhein-Neckar Löwen) for ten seasons, though he missed most of the 2002–03 and 2003–04 seasons due to a torn anterior cruciate ligament.