On an exciting final day, first-placed San Lorenzo (32 points) faced third-placed Velez Sarsfield (30) while the second- and fourth-positioned teams Newell's Old Boys and Lanus (both 30 points) squared off with all four teams capable of winning the title if the other result went their way.
Despite dominating shots and possession, Sarsfield could not find the goal that would have won them the title because of Newell's 2-2 draw with Lanus.
Lanus had the advantage with a superior goal difference to the other title challengers but suffered a blow when Pablo Perez secured Newell's opener not long after half-time.
But two minutes later, Lanus' Paolo Goltz restored parity by converting Max Velazquez's pin-point cross.
Newell's managed to poke their nose in front again on 67 minutes after Lanus' Carlos Izquierdoz scored an own goal.
However, Lanus were determined to stay in the contest and equalized in the 74th minute through Jorge Pereyra Diaz.
With no more goals in the contest, San Lorenzo's goalless draw in the other match allowed them to clinch their 15th championship.
It is San Lorenzo's first title since lifting the 2007 Clausura.
