Along with Emil Väre, Oskari Friman, Heikki Kähkönen and Aleksanteri Toivola, Taavi Tamminen was one of five wrestlers from the wrestling club Viipurin Voimailijat that dominated the lighter classes of the Greco-Roman wrestling scene at the start of the 1920s. Tamminen made his international début at the 1920 Olympic Games, where he reached the final of the Greco-Roman lightweight class, but lost there to his more famous clubmate Väre. Next Tamminen competed at the 1921 World Championships, where he won gold in middleweight. Tamminen was also Nordic lightweight champion in 1921 and won his only Finnish title in 1922 as a lightweight. After finishing his sporting career, Tamminen acted as a wrestling referee and also was the Finnish 1936 Olympic team masseur.