Leaders Boca Juniors preserved their unbeaten record but had to settle for a point in Argentina's Apertura.
Opponents Velez Sarsfield had lost three of their previous six home matches but they held out for a goalless draw.
The point earned by Boca extended their lead at the top of the table to eight points.
Lanus came from behind to win at bottom club Banfield and move up to third in the table.
Paolo Goltz's seventh minute own goal gave the home side the lead but Mariano Pavone and Carlos Izquierdoz scored to turn things around by half-time - and 2-1 was how it stayed.
Enrique Bologna's 87th-minute penalty gave Union Santa Fe a 2-1 home win over Newell's Old Boys.
Jeronimo Barrales opened the scoring for Union in the 49th minute, before substitute Martin Tonso equalised 13 minutes from time.