Gaston Fernandez scored a first-half penalty as Estudiantes stayed atop the Argentine league with a 1-1 draw at Colon on Saturday.
Esteban Fuertes opened the scoring for Colon in the fifth minute, but Fernandez sent goalkeeper Diego Pozo the wrong way from the spot to level the scores after 30 minutes.
The draw gave Estudiantes 26 points from 11 games atop the Apertura table, three ahead of Velez Sarsfield and Arsenal, which had a 3-2 win at Gimnasia earlier in the day.
Also Saturday, All Boys beat Independiente 3-1, and Banfield had a scoreless draw at home against Newell's Old Boys.
Games continue Sunday, with matches including Boca Juniors vs. Huracan and Godoy Cruz vs. River Plate.
Fuertes collected a long ball over the defense to give Colon the lead against Estudiantes, despite television replays suggesting he had controlled the ball with his arm.
Fernandez hit the equalizer from the penalty spot, firing low to Pozo's right while the goalkeeper dived the other way.
Earlier, Pablo Aguilar scored a late winning goal as Arsenal twice came from behind to beat struggling Gimnasia and move up to third in the standings.
Jorge Cordoba scored at the beginning of each half for Gimnasia, but Luciano Leguizamon got Arsenal's first equalizer in the 30th and Mauro Obolo leveled the scores for the second time in the 50th.
Aguilar headed in the winning goal just before the final whistle to keep Arsenal's title hopes on track. Gimnasia stayed third from bottom.
Meanwhile, Independiente slipped back into its losing ways with a 3-1 defeat at All Boys in Antonio Mohamed's second match in charge.
Mohamed oversaw a derby win against Racing Club in his opening game as coach last week, but Jonathan Ferrari scored in the fifth minute and Juan Pablo Rodriguez in the 15th to give newly promoted All Boys an early 2-0 lead.
Facundo Parra scored a header just before half time for Independiente, but Carlos Castiglione put All Boys further in front shortly after the restart.
Patricio Rodriguez was sent off for Independiente in the 82nd minute to snuff out any chance of a comeback.
The loss left Independiente fourth from bottom, while All Boys moved into the top half of the table.
Newell's Old Boys had Luciano Vella sent off in the 51st minute but moved to fourth on 18 points after holding on for a 0-0 draw at Banfield, which improved a place to ninth.
