San Lorenzo ended a four-match winless run with a 2-0 victory over Arsenal Sarandi in the latest round of the Clausura tournament.
San Lorenzo, who won the Inicial title in December, took the lead through Julio Buffarini's 30th-minute penalty and substitute Hector Villalba secured the points with his side's second 11 minutes from time.
The victory leaves San Lorenzo in fifth spot on 18 points, three adrift of leaders Colon.
Gimnasia La Plata are a further three points back in eighth spot following their 3-1 home win over 10-man Tigre.
Struggling Tigre took a 22nd-minute lead through Sergio Araujo, but Gimnasia hit back with goals from Ruben Barsottini (28), Franco Mussis (38) and Lucas Licht (61) to put themselves in control before the visitors lost Marcos Gelabert to a 66th-minute red card.