A 0-0 draw at Limon saw Carmelita fall to fifth on 15 points, one behind Deportivo Saprissa who were 2-0 winners away at Puma Generalena.
Alajuelense, though, have stormed up the standings and have four games in hand on leaders UCR even after their fourth straight win came in a 2-1 result at Santos de Guapiles.
Oscar Ramirez's men missed a large chunk of the domestic campaign due to CONCACAF Champions League duties, but they are four points behind UCR after a come-from-behind win.
The Estadio Ebal Rodriguez Aguilar hosts went ahead after Adrian de Lemos' 26th-minute goal, but 12 minutes later Alajuelense gained the lead.
Johan Venegas struck the equaliser for the Alajuela side, before Armando Alonso put the visitors ahead three minutes later.
Alajuelense are third in the table, with UCR and Cartagines both winning to hold the top two spots.
UCR held on for a 2-1 win at home to Perez Zeledon, while Cartagines needed a late Andres Lezcano goal to get past bottom club Uruguay 1-0.
Herediano came from behind twice on the road at Belen Siglo XXI, to earn a 2-2 draw against their struggling opponents.
Like Alajuelense, Herediano have been occupied with continental competition, and have played just six matches in the Torneo de Invierno for nine points.
