Aguirre Suárez made his name in Osvaldo Zubeldía's Estudiantes as an often violent full-back, playing alongside the more refined Raúl Madero. When Estudiantes conquered the 1967 "Metropolitano" title and was runner-up in the "Nacional" of the same year, it qualified for the 1968 Copa Libertadores, which it won. Estudiantes then engaged Manchester United F.C. for the 1968 Intercontinental Cup, which it won 2-1 on aggregate.