Pablo Repetto's league leaders made it three straight wins by edging Mushuc Runa 1-0 at the Estadio General Ruminahui del Valle de Los Chillos.
Mario Rizotto's 72nd-minute goal proved to be enough in front of their home fans.
Barcelona remain second and five points behind after battling to a 1-0 win at Emelec thanks to Ismael Blanco's 80th-minute effort.
Third-placed LDU Quito extended their unbeaten run to six matches with a 2-1 victory at Deportivo Cuenca.
Luis Canga and Cuenca's Juan Manuel Cobelli traded first-half goals before Diego Morales netted a dramatic late winner.
At the other end of the table, the bottom two both had wins.
Olmedo's second win of the season came at home to Deportivo Quito as Franco Mazurek scored the winner in a 1-0 victory.
Manta recorded their third victory of the campaign as Miller Castillo hit a brace in a 3-0 win at home to LDU Loja.
El Nacional and Universidad Catolica played out a 1-1 draw.
