Juninho scored in extra time as Tigres rallied to top eight-man Guadalajara, 2-1, on Saturday to return to the summit in Mexico's Clausura.
Omar Arellano scored in the 21st minute for Guadalajara, but Erick Torres was sent off before halftime and, after Carlos Salcido tied the match in the 72nd, Marco Fabian was sent off to leave Guadalajara with nine men.
Juninho's winner in the final minutes was followed by a third red card for the visitors, as Jesus Sanchez Garcia was sent off.
Tigres bounced back from just its second loss last week to win for the fourth time in its last five matches, and moved atop the standings by one point over Santos and Morelia.
Guadalajara lost its third straight, and is just five points off the bottom.
Cristian Benitez and Vicente Vuoso scored in the second half as America downed Santos, 3-1, on Saturday to open the door for Tigres to claim the top spot.
Edgar Lugo scored in the 77th minute as Morelia beat Pachuca, 2-1, on Saturday on the road to pull level with Santos.
Also Saturday, Carlos Orrantia scored in the 72nd minute as UNAM edged Atlante 2-1 to end a five-game winless run, Hugo Rodriguez helped Altas beat Monterrey 1-0, and Alberto Garcia Carpizo scored late as Queretaro tied San Luis 2-2.
On Friday, Jaguares extended its unbeaten streak to six games with a 0-0 draw against Tijuana, and Rubens Sambueza scored in the 87th minute as U.A.G. Tecos tied Puebla 1-1.
On Sunday, Christian Gimenez, Alejandro Vela and Javier Orozco scored as Cruz Azul defeated Toluca, 3-0.