Universidad Chile returned to winning ways in the Primera Division as their nearest rivals kept the pressure on.
A 2-0 loss at Colo Colo last time out put the league leaders under pressure, but they responded with a 2-1 victory over Palestino.
It saw them maintain their two-point advantage at the top, despite Colo Colo and Santiago Wanderers winning again.
First-half goals from Enzo Gutierrez and Patricio Rubio put Universidad Chile in control on Sunday before Cesar Valenzuela's effort after the break.
Martin Lasarte's men are two points clear of Colo Colo, who recorded a 2-0 victory at Union La Calera.
Gonzalo Fierro struck first before Esteban Paredes netted his 11th goal in what has been an impressive league campaign.
Paredes' goal came after Hugo Bascunan was sent off in the 58th minute for Union La Calera.
Santiago Wanderers, three points off top spot, claimed their fifth straight league win with a 2-1 victory at home to San Marcos.
Roberto Gutierrez's goal in the 36th minute led to an unusual celebration, as Wanderers players took a selfie.
Gutierrez scored again just moments later, but Wanderers were reduced to 10 men early in the second half when Pablo Tamburrini saw red.
Kevin Harbottle pulled a goal back for the visitors, who were unable to level and had Fernando Meza sent off late on.
Elsewhere, Mathias Riquero's brace guided Nublense to a come-from-behind 3-1 win over Union Espanola.
Pedro Munoz also scored twice as Universidad Concepcion overcame a Cobresal side that finished with 10 men 3-2.
Universidad Catolica battled past Audax Italiano 2-1 and O'Higgins were 3-0 winners over Huachipato.
Cobreloa and Deportes Iquique played out a thrilling 3-3 draw and Antofagasta drew 1-1 with Barnechea atfer the sides traded late goals.