German wrestler Georg Gerstacker of Nürnberg finished fourth at the 1913 World Greco-Roman Championship in lightweight, second at the 1914 European Championships in featherweight, and third at the 1921 European Championship in the same class. In 1924 Gerstacker was European Champion as a bantamweight. At the 1912 Stockholm Olympics he won the silver medal in Greco-Roman featherweight, losing the final against Finnish wrestler Kaarlo Koskelo. This was the only German wrestling medal in Stockholm.
In 1924, 1925 and 1927 Gerstacker was German Champion, placing second in 1926, and third in 1919 and 1922 (all as a flyweight). After World War I, he represented ASC Sandow Nürnberg. Gerstacker was also a good weightlifter, setting a world record in 1919 with 75 kg.