Christian Bermudez scored twice as Club America put one foot in the last four of the Clausura play-offs with a 3-1 win at Pachuca in their quarter-final first leg on Wednesday.
Jesus Molina opened the scoring after 38 minutes, two goals either side of half-time from Bermudez made it 3-0.
Pachuca then pulled one back through a Leobardo Lopez penalty 12 minutes from time to give them hope for Saturday's second leg.
Monterrey also claimed the advantage with a 2-1 win at ten-man Tijuana.
Goals from Jesus Zavala and Angel Reyna put the visitors 2-0 up and they may have expected to stretch that lead when Richard Ruiz saw red after 79 minutes.
Instead, the ten men rallied and pulled one back through substitute Raul Enriquez two minutes from the end.
