League leaders Santa Fe suffered their first defeat of the campaign, losing 1-0 to Millonarios, while second-placed Atletico Nacional succumbed to La Equidad 2-1.
Santa Fe and Nacional's losses saw the top six clubs finish the weekend within two points of each other, as Once Caldas, Junior, Boyaca Chico and La Equidad all won.
At the Estadio Nemesio Camacho on Saturday, Millonarios won thanks to Andres Cadavid's 42nd-minute goal with the 28-year-old defender side-footing the ball into the net from Dayro Moreno's driven cross, after a corner from the visitors was partially cleared by Santa Fe.
Nacional defender Alexis Henriquez missed a cross from La Equidad's Fredy Hinestroza and the ball found Leonardo Villagra, who set up Jose Moreno to score off the post.
La Equidad's second goal came in the 58th minute with Hinestroza scoring from the rebound after Villagra's initial shot was saved by Nacional goalkeeper Cristian Bonilla.
Diego Arias' stunning long-range free-kick in the 78th minute gave the home side some hope of a draw.
But as the minutes passed by, Nacional's frustration increased with Arias receiving a red card in the 94th minute.
In other results in Colombia's top tier, Atletico Huila defeated Alianza Petrolera 3-0, Fortaleza drew 2-2 with Patriotas Boyaca, Envigado won 2-1 at Deportivo Pasto and Itagui completed a 1-1 draw with Medellin.
