Gaetano Pirastu was an Italian boxer who started the sport as a teenager and won the Italian novice title at age 17, guided by Olympic silver medalist Primo Zamparini. In 1976 Pirastu competed as a lightweight at the Montréal Olympics where he was eliminated by decision in the first round by Puerto Rican Roberto Andino. Pirastu won the Italian amateur title three years later in Fano. He earned 24 international caps, but never turned professional. Instead, he taught and coached boxing at his club, Trionfo Genovese.