Portland and Real Salt Lake progressed to the last four of Major League Soccer's playoffs with victories on Thursday, eliminating Seattle and defending champion Los Angeles.
Portland, which won the first leg of its series 2-1 at regional rival Seattle, won the second leg 3-2 for a 5-3 aggregate victory.
Real Salt Lake, which lost 1-0 at Los Angeles in the opening leg, scored an equalizing goal and needed extra time to win 2-0 and take the series 2-1.
Portland broke through when Will Johnson converted a penalty in the 29th minute to go ahead 3-1 on aggregate.
Diego Valeri made it 2-0 in the 44th minute to all but secure a path to the last four for the Timbers, and Futty Danso scored a third goal with a header in the second minute of the second half to make it 5-1 on aggregate.
The Sounders did salvage some pride through DeAndre Yedlin's goal in the 74th minute and Eddie Johnson's goal soon after but could not get the additional two goals it needed.
The victory extended Portland's home winning streak to 16 games, and set up a Western Conference final against Real Salt Lake.
Chris Schuler's extra-time goal got the Utah club past Los Angeles, ending the Galaxy's bid for a third straight MLS Cup.
RSL reached the conference final for the third time in five years, with Sebastian Velasquez scoring in the 35th minute — his first MLS goal — and Schuler adding the clincher.
The Eastern Conference final will be between Sporting Kansas City and Houston.