Rodolfo "El Lobo" Fischer joined in 1963 the youth of the top club CA San Lorenzo de Almagro in the Argentine capital Buenos Aires. From 1965 he played in the first team of the club with which he won in 1968 under the Brazilian manager Elba de Pádua Lima "Tim" undefeated the Campeonato Metropolitano, the Metropolitan Championship - the first undefeated championship of any club in the history of professional football in Argentina. In 1969 he was top scorer of the Campeonato Nacional. In 1972 he won the both, the Metropolitan and the National championship with San Lorenzo. One of his personal highlights were his three goals he contributed to a 4-0 win over CA River Plate in April 1972.
From 1967 onward he also played 35 matches for the national team for which he scored 12 goals. His last match for Argentina was in July 1972 in the Maracanã in Rio de Janeiro at the Taça Independência, the Brazilian Independence Cup, where Argentina finished fourth. At this tournament he was, together with the Portuguese Joaquim Dinis number two in the scorer list.
After this tournament he stayed in Rio de Janeiro and played for four years for Botafogo FR, which paid one million Brazilian cruzeiros for him. Most prominent team member there was the World Cup 1970 winning player Jairzinho, and also Mário Zagallo coach of Brazil 1970 worked in Botafogo for some time in that period. In 1976 Rodolfo Fischer moved to north-eastern Brazil, where he joined for EC Vitória in Salvador da Bahia, playing under coach Tim once more.
From 1977 to 1978 he returned to Argentina and played again San Lorenzo, for which he scored altogether 141 goals in 271 league matches, which makes him fourth best scorer in the club's history.
1979 he went abroad once more to play for CD Once Caldas in Manizales, Colombia, for which he scored 11 goals in 40 league matches. In the years 1980 and 1981 he saw out his career back in Argentina with CA Sarmiento in Junín in the Buenos Aires Province and Sportivo Belgrano in Córdoba Province, both teams in the lower leagues.
These days Rodolfo Fisher lives on a farm in the interior of Argentina.