The "San Lorenzo", as it's more commonly called, was established in the city of Buenos Aires, and precisely at the "San Antonio" festive oratory directed by the beloved Salesian priest Lorenzo Bartolomé Martín Massa.
The Salesian priest wanted to offer his boys a new recreational space. According to Fr Massa himself, the colors of the team's shirt were taken from an image of Mary Help of Christians he kept in the oratory.
It all started with some youngsters from the neighborhood of Almagro who had started to meet in the street to practice that new sport played with feet: football. They would play at the intersection of México and Treinta y Tres Orientales, in the neighborhood of Almagro.
It was on the soccer field of the "San Antonio" oratory that the San Lorenzo played its first friendly matches, always on condition that its young players would participate in Sunday Mass.
The club slowly grew and Fr Massa was sent to continue his work of evangelization with other assignments at other destinations. And yet, even so, Fr Massa was always attentive to the club of his boys and those who continued to pass through his oratory.
Fr Massa died in Buenos Aires on October 31, 1949. A few days later, Fr Raul Entraigas, spiritual assistant of the San Lorenzo de Almagro club, wrote: "His love for the San Lorenzo de Almagro club was his life and his death, his joy and his drama. San Lorenzo was his spiritual son. Fr Massa did not love it as a father, but as a mother. He rejoiced for its triumphs and suffered for its defeats."
Today the San Lorenzo de Almagro is one of the main Argentine clubs and its activities have expanded, including, in addition to football, other disciplines, such as basketball, volleyball and hockey. And among the many fans, it also boasts the Successor of Peter, Pope Francis.
Source: Salesianos Cooperadores Argentina
https://www.infoans.org/en/sections/news/item/7705-argentina-san-lorenzo-de-almagro-a-club-with-salesian-roots#sigProId74d3a95727