Lanus drew 0-0 with Boca Juniors on Sunday to remain the Argentine first division leaders and undefeated after eight rounds.
The result leaves Boca, one of the preseason favorites for the title, down in 15th place after having won just one game this season.
In other Sunday matches, Boca's bitter rivals River Plate won 2-0 against Racing to improve into third place, two points behind Lanus, while second-placed Newell's fell to a 2-1 defeat against Colon.
Boca came close to breaking the scoreless deadlock when Juan Roman Riqueleme struck a right-foot shot from outside the area just past the far post in the 24th. A minute later, Nicolas Blandi took the ball past keeper Agustin Marchesin, but his shot rebounded back off the post.
River took the lead in the 12th minute when Leandro Gonzalez headed in from near the penalty spot from an in-swinging corner.
Manuel Lanzini stole the ball in his own half, sprinted forward, beat the last defender and finished a minute from fulltime to wrap up the game for River.
Emmanuel Gigliotti netted in the 52nd and then got Colon's second four minutes later. His first goal came when he appeared at the back post to get on the end of a free kick that swung in from the right, while the second he headed in from a long throw.
Horacio Orzan pulled one back for Newell's in the 58th.
In Saturday games, Rafaela beat Tigre 3-1, with Jonathan Lopez scoring twice in the last seven minutes.
Sebastian Carrera had given Rafaela the lead in the 7th, before Diego Cisterna equalized five minutes after halftime.
Velez Sarsfield drew 1-1 with San Lorenzo, with Ezequiel Rescaldani opening the scoring for Velez in the 55th minute and Leandro Navarro leveling the scored in the 80th.
The game between Union and Argentinos Juniors ended 0-0, as did the games between Godoy Cruz and Belgrano and Quilmes and San Martin.
On Friday, All Boys won 2-0 against Independiente with Brian Sarmiento and Angel Vildozo getting the goals.
On Monday, Arsenal plays Estudiantes in the last game of the eighth round.
