Emelec closed in on the Ecuador Primera A title after Independiente del Valle failed to capitalise on their slip-up.
LDU Loja held Emelec to a 0-0 draw on Wednesday but the league leaders maintained their six-point lead at the top after Deportivo Quito and Independiente del Valle drew 1-1.
With only two league matches remaining, Gustavo Quinteros' Emelec need one point to win the second stage.
Independiente del Valle fell behind on the half-hour mark in Quito as Alex Colon struck for the hosts.
Daniel Angulo responded almost immediately but the visitors were unable to find the winner they desperately needed.
Once in title contention, Universidad Catolica's winless run was extended to seven matches with a 3-2 loss at home to Deportivo Quevedo.
Federico Laurito's brace before half-time cancelled out Tito Valencia's early goal and looked to have Catolica on track for their first win since September.
But a Wilmer Godoy own goal and Valencia's second on 71 minutes saw struggling Quevedo to their second win in three matches.
Marwin Pita's goal saw El Nacional edge LDU Quito 1-0 and Omar Guerra's 83rd-minute winner helped Macara past Manta 2-1.
Deportivo Cuenca and Barcelona played out a 0-0 draw.