Argentinian champions River Plate posted their first win of the new Apertura season on Sunday by toppling Rosario Central 2-0.
River, who clinched a record 36th league title in May, went ahead in the 16th minute through Teofilo Gutierrez and sealed the points 10 minutes from the end courtesy of Leonardo Pisculichi.
There were also victories on Sunday for Racing Club and Boca Juniors.
Racing Club saw off San Lorenzo 2-0 - their second win in as many games - to go top of the fledgling standings. A goal at the end of each half, first from Luciano Lollo and then substitute Facundo Castillon, made the difference.
Boca, meanwhile, needed a last-gasp strike from Emanuel Gigliotti to triumph 1-0 at Belgrano Cordoba.