Tim Howard saved a pair of penalties in the shootout as the Colorado Rapids beat the LA Galaxy on spot kicks after their Western Conference semifinal finished 1-1 over two legs.
Giovani dos Santos skied his penalty attempt over the crossbar after Sebastian LeToux and Kevin Doyle converted their attempts to give the Rapids the upper hand from the off.
Howard saved kicks from Ashley Cole and Jeff Larentowicz to help his team win the shootout 3-1.
Shkelzen Gashi's 35th-minute wonder strike from long range put the hosts back on level terms with LA for the tie, following the Rapids' 1-0 loss at StubHub Center on Oct. 30.
Gashi's strike was one of few highlights in an otherwise dull 90 minutes at Dick's Sporting Goods Park, with Dominique Badji spurning the best chance for Colorado in the second half after Jermaine Jones played him through on goal.
Colorado continued to push in vain and the game went to extra time with neither team having many clear-cut chances in regular time.
The match opened up in the extra frames, with Rapids substitute Marlon Hairston troubling LA's Jelle van Damme on the right flank on two occasions, but unable to find a winner.
Badji again had a golden chance in the first extra-time period, but his header from a Eric Miller cross went right into the arms of LA's Brian Rowe.
Colorado's Marco Pappa came on for Badji in the 112th minute and nearly provided the assist for the match winner, but his cross into the area sailed over his teammates' heads as the match went to penalties.
The Rapids will face the winner of FC Dallas and Seattle Sounders in the conference semis in the day's late game.