Estudiantes defeated Boca Juniors 1-0 on Saturday to move within a point of the lead in Argentina's Apertura football championship.
Estudiantes have 16 points and Velez has 17. Estudiantes have played one fewer game than the leaders.
San Lorenzo remained on 15 points after a 2-0 loss to Colon.
In two other matches Saturday, substitute Gonzalo Vargas scored in the 77th minute to give Argentinos Juniors their first victory of the season with a 1-0 win over Banfield. It was Banfield's first loss. for Argentinos Juniors.
Santiago Hoyos scored the lone goal to lead Lanus over All Boys 1-0.
Marcos Rojo scored in the first minute for Estudiantes, which turned out to be enough at the Jorge Luis Hirschi stadium in La Plata. It was a rebound for Estudiantes, which was upset last week 2-1 by All Boys.
The biggest victory of the day was probably for Argentinos Juniors, the defending Clausura champions.
"It's clear that the survival of a coach depends on winning," Argentinos Juniors coach Pedro Troglio said. "This is a relief. It's been three tough months and it was important to win."
Damina Diaz and Joaquin Larrivey scored in Colon's victory over San Lorenzo.
On Friday it was: Velez 3, Olimpo 0; Independiente 1, Gimnasia 0.
On Sunday: River Plate vs. Quilmes, Arsenal vs. Newell's, Godoy
Cruz vs. Huracan, Tigre vs. Racing Club.
