Career
Club career
After stints at Argentinos Juniors and Club Atlético Lanús in Argentina and Club Toluca in Mexico, Gnavi arrived in Australia in 1974 to play for Pan Hellenic in the New South Wales State League. In 1977 he transferred to Saint George for $9,000. He played 68 National Soccer League matches for Saint George between 1977 and 1980.
International career
Gnavi played one match for Australia in 1975 against the Union of the Soviet Socialist Republics.