Atlante beat Morelia 2-1 as former Monarcas forward Rafael Marquez Lugo scored twice on his former club.
Marquez Lugo scored two first-half goals as Morelia never recovered.
With the loss, Morelia squandered a chance to take of the top spot of Group 2 and instead tightened the group. Group rivals Monterrey and America each lost road games but Monterrey remain atop the group with 23 points while Morelia have 22. America are in third with 21 and Pachuca, who beat America, have 19 points. Thus, four points separate four teams in the group.
Atlante's Santiago Solari helped set up the first goal. Solari beat Jorge Gastelum to the penalty area and was dragged down by Gastelum.
Marquez Lugo then took the penalty kick and buried it past Morelia's Moises Muñez.
Iin the 25th minute, Solari and Marquez Lugo teamed up in a more traditional manner. Solari found Marquez Lugo from the left side and the former Morelia man buried his shot into the back of the net.
Morelia tried to mount a comeback and did well to get a goal. In the 28th minute, Mauricio Romero sent a free kick on goal and slipped the ball through the wall and past Federico Vilar for their first gaol of the game.
But Morelia tried and were unable to notch the equalizer. Atlante even tried to help out Morelia's cause. Horacio Peralta was sent off in the 68th minute.
Not even with Miguel Sabah on the field - Sabah started the game on the bench but came into the match in the 58th minute - could Morelia do damage.
Atlante held on and improved to 4-5-1. With a game in hand, Atlante could move close to Cruz Azul for the second-place spot in Group 3.
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