Lanus continued their perfect start to the Argentinean Clausura season with a third straight victory over Velez Sarsfield.
The home side claimed a 1-0 victory, with Silvio Romero on target in the 36th minute.
Quilmes moved to six points with a 3-0 away win at Union Santa Fe.
Jacobo Mansilla (7) and Fernando Elizari (41) did the damage before a last-gasp third from substitute Sebastian Romero.
All Boys claimed their first win of the season, 2-0 over visiting Boca Juniors.
Oscar Ahumada opened the scoring in the 52nd minute and Angel Vildozo secured the points with a 61st-minute penalty.
Argentinos Juniors continued their unimpressive start to the Clausura season with a third straight defeat at the hands of visiting Arsenal Sarandi.
The game was goalless until Julio Cesar Furch netted in the 66th minute, with Sarandi's second following three minutes later through Carlos Carbonero.
Leandro Barrera got a consolation for Argentinos with four minutes remaining.
San Lorenzo drew 1-1 at Estudiantes in the other fixture, giving the home side a first point of the campaign.
Duvan Zapata put Estudiantes in front after seven minutes, Santiago Gentiletti grabbing the equaliser 11 minutes from time.
