Boca, Velez and Tigre notch wins
Boca Juniors, Velez Sarsfield and Tigre each picked up their second win in three games at the start of the new Clausura campaign.
Velez Sarsfield have the honour of topping the nascent league table on goal difference after holding off Arsenal Sarandi's fightback to win 3-2.
Augusto Fernandez and Juan Manuel Martines struck within two first-half minutes, the latter from the penalty spot, and when Fernandez notched his second in the 62nd minute the match looked over.
But Emilio Zelaya and Luciano Leguizamon cut the deficit to one and Velez had to hang on for seven minutes plus stoppage time before victory was secured.
Tigre won 2-0 at Godoy Cruz after a dramatic finish to a match in which they took a first-half lead through Carlos Luna.
An incident in the 83rd minute saw both Godoy's Ruben Ramirez and Tigre Mariano Echeverria sent off before substitute Leandro Diaz grabbed a winner three minutes later.
Boca Juniors beat Newell's Old Boys by the same scoreline, Dario Cvitanovich scoring on the stroke of half-time before Juan Roman Riquelme made the game safe late on.
The victories leave all three teams on seven points, along with All Boys.
Banfield won 2-1 at Racing Club in the day's other game. Teofilo Gutierrez's early penalty gave Racing Club a lead which was quickly cancelled out by Andres Chavez's 12th-minute strike and, after Gutierrez was sent off with 10 minutes remaining, Banfield sub Hernan Lopez grabbed a last-minute winner.