From his flagship the galleon "Ritter Sankt Georg", he commanded the Polish fleet during its only major encounter with the Swedish fleet at the Battle of Oliwa on 28 November 1627. In this action the Poles captured the Swedish galleon "Tigern" and forced the crew of another, the "Solen", to scuttle their vessel. Dickmann, now aboard the captured "Tigern", was killed when a cannonball, possibly fired from galleon Pelikanen, smashed his legs. His funeral, with full honours, took place at St. Mary's Church in Danzig on 2 December.