The Centurions' first-ever game was against local rival Rhein Fire. Cologne lost 25-26. The Centurions' inaugural season finished with a 4-6 record.
On 21 February 2006, the Centurions named David Duggan as their new head coach. He replaced Darryl Sims, who was on the verge of his first season in the position but instead was pursuing an opportunity in the NFL. Peter Vaas, a two-time World Bowl-winning coach with the Berlin Thunder, had occupied the job in the team's first two seasons. The Centurions were the only NFL Europe team that never won a World Bowl.