Monterrey advanced to its third straight CONCACAF Champions League final, where it will face Santos Laguna for the second straight year.
The Rayados won the first leg 2-1, with Aldo De Nigris scoring one and creating another. Los Angeles needed at least two goals to advance. None came.
"We're disappointed with the result tonight, but we lost to a very good team," LA coach Bruce Arena said. "We may have lost this series in the last 10 minutes last week in Los Angeles. We made it very difficult for ourselves. Tonight was going to be hard because of the way we played in the last 10 minutes last week.
"Having said that, Monterrey is an excellent team – deserving winners."
With LA chasing the series, Landon Donovan made his first start since returning from a sabbatical. Not even the all-time leading U.S. national team goalscorer could help matters, with the Galaxy blanked.
"This competition is difficult for MLS teams right now," Arena said. "We don't have our full fitness at this time of year, and certainly that's the case for Landon. But I thought Landon did very well to survive 90 minutes tonight."
In the 63rd minute, De Nigris put the ball past Carlo Cudicini. However, Neri Cardozo was offside in the build-up.
De Nigris' goal that came with 10 minutes remaining stood. Severo Meza angled the ball into the box. Cesar Delgado cut it back with a no-look one-touch pass, and De Nigris drilled it between Cudicini's legs.
Monterrey will meet Santos Laguna in an all-Mexican final for the second straight year as it aims for a third consecutive CCL championship, something no team has accomplished since the competition moved to its current format.
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