 In 1975 San Telmo finished third in Primera B, therefore the team qualified to play the playoffs to promote to Primera División, which finally achieved.Although being promoted to the first division, San Telmo would be relegated in the next season.Nevertheless, the team that played in the top level during 1976 wrote a memorable page in the history of the club on May 25, 1976 when it defeated Boca Juniors by 3–1 at Huracán's stadium.