The playoff was scheduled for 27 October 1912 at the Quilmes A.C. Stadium in the homonymous city, where San Isidro defeated Quilmes 2–1,[2] to win their second consecutive Copa de Competencia trophy.[3][4]
It was the first Copa Jockey Club final defined in a playoff match.[5]
On the other hand, Quilmes entered directly to the quarterfinal, where the team defeated Belgrano A.C. 2–1 in Belgrano, then eliminating Tiro Federal 5–1 at home in semifinal.[2]