A 0-0 draw in the first leg left it all to play for on Wednesday. Monterrey came out attacking as they looked to put their home field advantage to good use, but although they had more possession and more chances, it was Alianza who had one of the more dangerous opportunities with a shot from close-range that ended up skied over the crossbar.
It looked like the Rayados would find the breakthrough in the 50th minute, when they earned a penalty kick, but Víctor García made the save on Nicolás Sánchez to keep the game 0-0.
Alianza looked to grab a goal against the run of play and Óscar Cerén came close, only for Marcelo Barovero make a fingertip save.
Finally, just when it was looking like overtime was looming, the hosts were given another golden opportunity to take the lead as they earned another penalty kick in the 85th minute after Dorlan Pabón was fouled in the box.
Nicolás Sánchez stepped up once again and this time he converted to give Monterrey the 1-0 (1-0 aggregate) lead.
With the 1-0 (1-0) win, Monterrey advances to the quarterfinals to face the winner of the Herediano/Atlanta United series, while Alianza is eliminated.
Monterrey: Marcelo Barovero, Nicolás Sánchez, César Montes, Jesús Gallardo, Miguel Layún, Carlos Rodríguez (Ángel Zaldívar 75’), Rodolfo Pizarro (Celso Ortiz 89’), Jonathan González, Rogelio Funes Mori, Avilés Hurtado, Maximiliano Meza (Dorlan Pabón 58’).
Alianza: Víctor García, Iván Mancia, Henry Romer, Jonathan Jiménez, Ruben Marroquin, Marvin Monterrosa (Herbert Sosa 71’), Narciso Orellana, Issac Portillo, Irving Herrera (Bladimir Díaz 45’), Diego Benitez (Juan Carlos Portillo 68’), Óscar Cerén.