San Martín has only played two seasons in the Argentine top flight. Its first appearance was in the 1970 Nacional championship, finishing bottom of the group after winning only four of 20 games. The squad gained the promotion to the first division for the third time during the 2010–11 season, after beating Club de Gimnasia y Esgrima La Plata 1–0 and later 1-1 on aggregate in the playoff for the second automatic promotion place.