Lowly Tigre held Lanus to a scoreless draw at home despite ending the match with 10 players, after Gaston Diaz's second-half red card.
In a frustrating result for Lanus coach Guillermo Barros Schelotto, the draw left his side in sixth with 26 points, four adrift of Gimnasia and just behind fifth-placed Estudiantes on goal difference in the Primera Division table.
Tigre produced the better chances to score at the Estadio Ciudad de Lanus in the catch-up game on Wednesday with the visitors producing five shots on target compared to the hosts' two, however, neither team was able to beat their opposing goalkeeper.
Diaz's expulsion with 12 minutes remaining gave Lanus some hope of notching a late winner but the reigning Copa Sudamericana champions were unable to breach Tigre's defence and were forced to settle for a draw against the 15th-placed club in Argentina's top tier.
The draw ended Tigre's two-game losing streak and took them a point ahead of the next two teams in the table - Racing Club and Atletico Rafaela.
Lanus have collected four points in their past three games to drop to sixth with their goal difference (0) keeping them behind Estudiantes (plus five).
Godoy Cruz (28 points, plus six) and River Plate (28, plus five) are Gimnasia's main rivals at the top of the table, while Colon sit fourth on 27 and a plus four goal difference.
Gimnasia, who have won their past six straight games, have a goal difference of plus eight.
Get the best features, fun and footballing frolics straight to your inbox every week.
Thank you for signing up to Four Four Two. You will receive a verification email shortly.
There was a problem. Please refresh the page and try again.