Enzo Perez and Gabriel Mercado scored second-half goals to give Estudiantes a 2-0 home win over Racing Club on Saturday and into the lead of the Argentine Apertura tournament with a game in hand.
Unbeaten Estudiantes has 13 points from five games, ahead of Velez Sarsfield on goal difference. Velez shared a 0-0 draw earlier in the day with third-placed San Lorenzo.
Elsewhere on Saturday, Banfield twice came from behind to draw 2-2 at Huracan, while Godoy Cruz was a comfortable 4-1 winner at Lanus.
On Friday, Tigre had a 2-0 win against Gimnasia La Plata, while Colon drew 1-1 with All Boys.
Matches continue Sunday with Argentinos Juniors vs. Newell's Old Boys, River Plate vs. Arsenal de Sarandi, Independiente vs. Quilmes and Olimpo vs. Boca Juniors.
Estudiantes had the better of a tight first half against Racing Club, with Carlos Auzqui's shot saved at point blank range by goalkeeper Jorge De Olivera in the 35th minute.
De Olivera tipped a dipping drive from the edge of the box by Rodrigo Brana over the bar in the 39th minute and Juan Pereyra also went close with a header over the bar from a corner in the 40th as Estudiantes continued to press.
Racing's best chances were limited to a back-post header from Pablo Luguercio in the 30th and a long range shot that went wide from Jose Luis Fernandez immediately after.
Racing defender Lucas Aveldano forced the ball over the line in the 32nd minute but the goal was disallowed for offside.
It took just 28 seconds of the second half for Estudiantes to take the lead. Mercado whipped a cross into the box from the right for Perez to side-foot across De Olivera and inside the far post.
Mercado scored the second goal himself with a shot powered past De Olivera's dive from inside the box in the 56th minute.
Estudiantes captain Juan Sebastian Veron almost scored a third with a swerving free kick tipped over the bar in the 62nd minute, but his side had already done enough to finish the day atop the standings.
Earlier in the day, Rolando Zarate twice gave Huracan the lead against Banfield with a penalty in the ninth minute and a second goal in the 56th.
In between, Marcelo Carrusca pulled Banfield level, before Emilio Zelaya produced a second equalizer for the visiting team in the 62nd.
Meanwhile, Lanus was outclassed at home by Godoy Cruz despite Mario Regueiro's 28th-minute penalty equalizing David Ospina's opener in the 10th.
Godoy Cruz cut loose in the second half with goals from Ariel Rojas on the hour mark, Jairo Castillo in the 77th and Diego Villar in the 82nd.
