Dayro Moreno's 20th-minute goal helped Millonarios to a 1-0 win at bottom side Fortaleza and within two points of top spot.
Atletico Nacional were held to a second straight draw as third-placed Once Caldas kept them goalless on Saturday.
Moreno's tap-in was all Millonarios needed against a Fortaleza side who have just one win in 12 games.
Santa Fe were the third of the top four teams to fail to score in the 12th round as they drew 0-0 at home to Boyaca Chico.
La Equidad claimed their first win in a month as Fredy Hinestroza's goal saw them edge Atletico Huila 1-0.
Itagui and Junior also only needed a goal each to claim 1-0 victories over Deportes Tolima and Envigado respectively.
Deportivo Pasto crushed Uniautonoma 4-0 on the back of Bosco Frontan's brace, while German Cano's double saw Medellin past Deportivo Cali 2-0.
In a six-goal thriller on Saturday, Patriotas Boyaca and Alianza Petrolera played out a 3-3 draw.
