Johan Andersson from Göteborg competed in the middleweight B class of Greco-Roman wrestling at the 1912 Stockholm Olympics. After a victory in the first round, both Andersson and his opponent, the Russian August Pikker, were disqualified for passivity. Andersson was eliminated after round four and two more losses by fall. His first major international tournament was the unofficial World Championships in Helsinki in 1911, where he placed eighth. In 1912, he earned his only national title in the light-heavyweight class representing Örgryte IS.