It was left to Monterrey's Humberto Suazo to plunge in the final fork as he provided the game's only score in the waning moments of the opening half.
From the opening kick, an aggressive Real Salt Lake attacked from all angles, and it opened up a few real early chances. Fabian Espindola was especially effective.
Yet he and the rest of his attacking teammates, as they would be for the entire match with Monterrey, were just off the money.
Espindola fired off three shots within the first 10 minutes, including one from inside the 18-yard box that he couldn't curl around goalkeeper Jonathan Orozco.
"We missed in the beginning of the game, but the last five minutes we had chances," RSL midfielder Javier Morales said. "We didn't play good tonight."
Salt Lake's final shot of the first half, an effort by Andy Williams, came in the 32nd minute.
Slowly, inexorably, Los Rayados gained control. RSL ran out of chances and out of gas. From the 33rd minute on, Monterrey picked up the pace with five good chances.
The final, Suazo's goal, was a typical striker's effort, cleaning up the rebound amid the jumble inside the box. RSL goalkeeper Nick Rimando, prone on the ground, had stopped Sergio Santana's effort, but could do nothing but watch helplessly as the ball and a possible FIFA Club World Cup berth skipped by and into the net.
• Real Salt Lake's Fabian Espindola misses three shots in the opening 10 minutes.
• RSL doubles Monterrey's shot attempts, 16 to eight.
• Monterrey takes one shot on goal the entire game and scores.