Emelec won 2-1 away to Barcelona on Saturday to keep the pressure on leaders LDU Loja in the Ecuador Primera A.
Loja maintained their unbeaten start to the Primera A season with a 1-0 win away to Deportivo Cuenca on Friday with Jonny Uchuari scoring the only goal of the game.
That win took Loja to 14 points at the top of the Ecuadorian league standings, while Emelec moved up to 13 with a game in hand after their victory in the Clasico del Astillero - or the Shipyard Derby - on Saturday.
Barcelona hosted their bitter local rivals at the Estadio Monumental Isidro Romero Carbo in Guayaquil with both sides scoring in the first half.
Osbaldo Lastra opened the scoring for Emelec in the 34th minute with a header from a corner but Cristian Penilla ensured Barcelona were level at half-time, taking advantage of an error in the visitors' defence to score.
Emelec took the honours over their Guayaquil rivals thanks to Lastra's 69th-minute goal, when the defensive midfielder knocked the ball home from Fernando Gaibor's free-kick.
In Cuenca, Loja claimed their fourth win of the season with Uchuari scoring in the 74th minute, converting from the edge of the box past the home side's onrushing goalkeeper after Fabricio Guevara's initial shot was partially blocked.
Olmedo and Independiente del Valle both remain in contention after wins over Universidad Catolica and Manta, respectively.
In Quito, Olmedo snatched all three points against Catolica, thanks to Marco Mosquera's 92nd-minute winner in a 2-1 victory.
Olmedo hit the front in the seventh minute through Romario Caicedo but Catolica looked set to claim a draw when Henry Patta struck with seven minutes remaining, until Mosquera's stoppage-time goal clinched victory for the visitors.
The win took Olmedo to 11 points, ahead of Independiente on goal difference after the latter defeated Manta 1-0 on Saturday.
In other results, Deportivo Quito drew 1-1 with local rivals LDU Quito and El Nacional won 1-0 away to Mushuc Runa.