In April 1993, Olsen moved to his former team 1. FC Köln which he saved from relegation, when coming to its aid in the last six games of the 1992–93 Bundesliga season. In his time in Germany he would become a certified coach, earning his "Fußball-Lehrer-Lizenz" diploma in 1993. For two seasons he had the club positioned somewhat safely from relegation, despite not having any especially good players. At the start of the 1995–96 season, Köln were eliminated in the DFB-Pokal by an amateur team from Beckum, and Olsen was fired in August 1995.