Juan Díaz learned his boxing at the famous Manuel Sánchez Boxing Club in the northern Chile city of Iquique. A member of the Chilean Royal Air Force, he won the national featherweight title three years in succession 1957-59, and was the Latin American champion in the first of those years. Díaz had to fight his fellow Iquiqueño Mario Gárate in the preliminary competition for a place at the 1960 Rome Olympics. Gárate was favourite, having won the bronze medal at the 1959 Pan American Games in Chicago. However, Díaz won and went to Rome where he enjoyed a unanimous decision against the Australian Danny Males before losing a split decision to Switzerland’s Ernst Chervet in the second round. Díaz turned professional in 1963 and had just three pro contests, with a 1-1-1 record. His son Eduardo was a footballer and played for Deportes Iquique before later becoming a coach. “Chucheta” Díaz died just nine days before his 85th birthday.
Chile