Leaders Guadalajara were held to a 1-1 draw by 10-man basement dwellers Atlas.
Fernando Quirarte's side could not have wished for a better chance to move further clear at the head of the table when Luis Ramos was sent off six minutes before the break.
They thought they had taken it too when Erick Torres put them ahead (54), but Lucas Ayala had other ideas and levelled (78).
Lowly Atlante scored three goals in the last eight minutes to earn a thrilling 4-4 draw with Morelia.
Rafael Marquez Lugo gave Morelia the lead and the visitors were 2-0 ahead by the break when Edgar Luga netted.
Luis Venegas then put through his own net to make it three and, although Osvaldo Martinez netted for Atlante (75), Luzo looked to have sealed things with 10 minutes left.
But Christian Bermudez gave Atlante hope, Martinez`s penalty after Marvin Cabrera was sent off gave them a chance and Venegas' injury-time leveller and redeemer gave them a point.
Jaguares also scored four goals but they managed to keep a clean sheet as they saw off the Unam Pumas 4-0 to go second.
Jackson Martinez got things going with 10 minutes gone, Edgar Andrade made it two and Martinez`s penalty three, with Andrade wrapping things up with a minute left.
Pachuca got the better of Monterrey by the same scoreline.
Enrique Esqueda scored twice, with Felix Burja netting in between times, while Maura Cejas added a fourth.
An own goal from Santiago Hoyos set Tigres Monterrey on their way to a 2-1 win over Santos Laguna.
The unfortunate incident occurred four minutes before half-time and, although Christian Suarez levelled on the stroke of the whistle, Alberto Acosta won it.
