Göpf Kottmann started rowing at age 13, with the Belvoir Ruderclub in Zürich. He became one of Switzerland’s most versatile rowers, winning national titles in eight different events. In 1954 and 1955, he won the European title in the coxed pairs with Rolf Streuli and coxswain Walter Ludin. The boat was unable to compete at the Melbourne Olympics, as Switzerland was one of the few countries boycotting the Games due to the Hungarian Revolt. They won two more medals at the Europeans but Streuli and Kottmann also joined the national quadruple sculls boat, winning a European bronze in 1957. With his team mates retiring from rowing, Kottmann switched to the single sculls. In 1963, he won the Henley regatta, and reached the World Championships final, where he placed sixth after leading at the halfway point. At the Tokyo Olympics, he was more successful, taking home a bronze medal. Besides rowing, Kottmann was also an active bobsledder. As a crew-member of Max Angst, he won a World Championship bronze in 1961, as well as three Swiss titles in the four-man sled. Just a month after winning his Olympic medal, Göpf Kottmann drowned in Rhine while taking part in a military exercise as a frogman.