Emelec slumped to a 2-0 defeat against Carlos Sevilla's side last weekend and were then beaten 2-1 by Brazilian side Flamengo in the Copa Libertadores on Thursday.
But Gustavo Quinteros' charges ended a poor week on a high note as they swept aside fourth-placed El Nacional with a clinical performance.
Cristian Nasuti set them on their way with a goal after 27 minutes, then Miller Bolanos stunned the visitors with a second goal two minutes later.
Jorge Valencia halved the deficit 13 minutes after the break, but Marcos Caicedo added a third goal from the penalty spot 10 minutes from time before further strikes from Angel Mena and Javier Charcopa added insult to injury.
That victory ensured Emelec maintained their one-point advantage over Independiente Del Valle, who had taken over at the summit with a 2-1 win over struggling Mushuc Runa on Friday.
Maximiliano Barreiro gave Runa a sixth-minute lead and they looked set to pull off a shock win before Junior Sornoza kept his nerve to equalise from the spot seven minutes from time and Gabriel Cortez won it a minute later.
Third-placed LDU Loja slipped up on Saturday as they were consigned to a 4-2 defeat at Manta, who were indebted to two goals from Jorge Palacios Avila.
There was more misery for bottom-of-the-table Deportivo Cuenca, who have only won one league victory to their name this season after they were beaten 1-0 at home by Deportivo Quito.
In the other games to be played on Sunday, Armando Wila scored both goals in Universidad Catolica's home victory over Barcelona and Olmedo were 1-0 winners of LDU Quito.
‘After Manchester City’s recent form, maybe they’re the underdogs against Manchester United!’ Former Red Devils defender on this weekend’s derby
‘Arteta, Alonso, Emery, me… none of us were physical players – we needed the understanding of the game. That probably helped us move into management’: Premier League boss reveals reasons for natural career progression
