An early headed goal from Rodolfo Pizarro handed Monterrey a 1-0 victory over Cruz Azul on Wednesday in Estadio BBVA Bancomer in the first leg of the Liga MX 2018 Apertura semifinal.
Monterrey came out on the front foot and was rewarded in the fourth minute, when Dorlan Pabon crossed from the right wing to Pizarro, who was free to head in at the near post.
Cruz Azul is looking for its first title in over 20 years and finished the regular season in first position, but was out-worked by Monterrey and only created one real chance, when Marcelo Barovero tipped an Elias Hernandez header over the bar in the 19th.
The Hernandez effort was Cruz Azul's only attempt on target over the 90 minutes.
Monterrey striker Rogelio Funes Mori came close to doubling his lead with a shot from inside the penalty area 20 minutes from the end.
Cruz Azul had more possession over the 90 minutes, but failed to create, partly due to how intense Monterrey was in winning back the ball and disrupting the opposition.
Cruz Azul had been the favorite for the semifinal series, but will have to overcome the deficit on Saturday in Estadio Azteca in the second leg.
Pumas host Club America in a Mexico City derby on Thursday evening in the other Apertura semifinal first leg.