Sebastian Arosa's first-half goal was enough for Olimpia to beat Cerro Porteno and go seven points clear at the top of the Apertura.
The defeat also marked the last match in charge for Cerro head coach Mario Grana, who said: " The team played well and I am grateful for all the work they did. We have had 60 per cent good results."
In a game played over 300km from Asuncion and watched by 20,000 fans, Arosa's excellent strike, his first goal for the club, proved to be the difference.
With the win, unbeaten Olimpia moved seven points clear above Cerro, who are now just a couple of points in front of Libertad.
Libertad were impressive 5-1 winners at Rubio Nu on Monday evening, with four goals coming in 25 second-half minutes.
Pablo Velazquez gave Libertad the lead before the interval and Jose Nunez, Nester Camacho (2) and Miguel Samudio were all on target in the second period.
Cesar Llamas scored a late consolation from the penalty spot for Rubio, who had not lost in three outings prior to the match.
Nacional Asuncion's 2-1 defeat at Sportivo Luqueno spelt the end for coach Javier Torrente, who resigned because he said he was not achieving the objectives he set out to.
"A change, the arrival of a new coach can bring more energy to the club," he commented. "I'm sure the team will end up fighting for the championship."
Asuncion are fourth in the table after the loss, while, in the battle at the bottom, Independiente FBC beat Tacuary 2-1 thanks to goals from Emanuel Biancucchi and Jose Baez.
Sol de America halted their winless run with a 2-0 victory at Sportivo Carapegua, the goals coming in either half from Reinaldo Ocampo and Sergio Escalante.
Meanwhile, Cerro Porteno PF beat Guarani 2-1 thanks to efforts from Miguel Godoy and Rogerio Leichtweis.