Club Atlético de San Isidro (CASI) is a sports club in Acassuso, in the Province of Buenos Aires, Argentina, with a rugby section. In 2026 its men's first team plays in the TOP 14 Superior competition of the Unión de Rugby de Buenos Aires (URBA).
History
The club was founded on 24 October 1902 through the merger of two clubs.
Ground
The club's address is Roque Sáenz Peña 499, Acassuso.
Teams and training
The rugby section has a senior squad (plantel superior) and youth (juveniles) and children's (infantiles) divisions. As of August 2026, the senior squad (plantel superior) trained on Mondays, Tuesdays and Thursdays from 20:00 to 22:30 at Boya 1 for the 2026 season. Membership of the club requires an admission application.
Club life
The club's line is "Vivamos el Club valorando su tradición con armonía y respeto" ("Let us live the club, valuing its tradition with harmony and respect").