 During the 2011–12 season, his 21st professional season and second year as captain of Eisbären Berlin, he suffered a season ending concussion after 23 games.Whilst still suffering from post-concussion symptoms 14 months later, and other non-related injuries, Ustorf announced his retirement at the tail end of the 2012–13 season on March 7, 2013.On December 28, 2016, he had his jersey number 14 retired by the Eisbären side.