[1] At international level he played for East Germany national team in 63 matches scoring 15 goals, and was a participant at the 1974 FIFA World Cup.

After the Second World War Ducke's family left their home in Sudetenland to settle in Schönebeck near Magdeburg, Germany.

Following both his father and his three brothers into football Ducke began his career in 1950 for a Betriebssportgemeinschaft (English: Company sports community) Motor Schönebeck whose first men's team played in the Saxony-Anhalt league.

Only after convincing performances in five international matches with the East German youth team from 1959 to 1960 Jena was interested in Ducke again.

As a center forward on the team Ducke, within 18 years, scored 153 goals which was a significant contribution to their success.

This led the league coaches, in a survey by the newspaper Deutsches Sportecho, to nominate Ducke as the best striker of the 1962/63 season.