Duje Bonačić was active in numerous sports during his youth, including swimming, water polo, sailing, handball, and track and field athletics. It was rowing, however, that most grabbed his interest and soon he was focusing his attention primarily on that activity. He was afforded more opportunities for competition after World War II, which culminated in his selection to represent Yugoslavia at the 1952 Helsinki Olympics. There, the underdog team of Bonačić, Velimir Valenta, Mate Trojanović, and Petar Šegvić competed in the coxless fours event and captured a surprise victory. This was the only gold medal in rowing ever won by Yugoslavia. This was the pinnacle of Bonačić’s sporting career, as he soon graduated with a degree in geography and ended his active competition. He then became a school teacher in the sciences, particularly in geography, oceanography, and meteorology, as well as an educational administrator and advisor. His mother’s nephew, Boris Gregorka, was a member of the Yugoslavian gymnastics team that won a bronze medal in the all-around at the 1928 Amsterdam Games.