Firpo

Usulután had waited since the Clausura of 1998–99 for another Primera División trophy, and the 2025 Apertura final against Alianza did not make the wait easy.

That earlier run, from the 1988–89 season to 1998–99, produced seven championships in eleven years and remains the period by which everything else at the club is measured. Founded on 21 January 1923 — some club histories trace the line back further, to a side called Tecún Umán active from 1908, though the connection is not settled — Firpo marked its centenary in 2023, two years before the 2025 title gave the anniversary a proper coda.

Their fixture with Alianza FC, the Clásico Joven, carries the weight of San Salvador against the provinces rather than a simple rivalry of proximity — Usulután is well outside the capital, and the meetings are read locally as that contest as much as a football one.