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Sandy, UT (SportsNetwork.com) - The Portland Timbers will aim to continue their magical season on Sunday when the club travels to Rio Tinto Stadium to face Real Salt Lake in the first leg of the Western Conference finals.

After finishing the regular season with 57 points and the top seed in the ultra-competitive West, first-year head coach Caleb Porter has his side ready to vie for their first appearance in MLS Cup after vanquishing Seattle Sounders FC in the semifinal round.

The Timbers grabbed the upper hand in the series after earning a 2-1 first-leg victory over Seattle at CenturyLink Field, putting the Sounders in a hole heading back to Jeld-Wen for Thursday's return fixture.

Playing in front of their home fans, Portland raced out to a quick lead in the 29th minute when Will Johnson converted a penalty kick and Diego Valeri fired one home to give the hosts a 2-0 and 4-1 aggregate lead at the intermission.

Mamadou Danso made it 3-0 to the Timbers in the 47th before Seattle mounted a brief comeback with goals from DeAndre Yedlin and Eddie Johnson two minutes apart to make it 3-2 to Portland with 15 minutes to play.

But the Timbers were able to stem the tide and hold on for the 5-3 aggregate win, sending Porter's men to Real Salt Lake for the first leg of the Western Conference final.

Porter explained what it meant for his team to reach the Conference finals:

"I think it means that we're three games away and we have two teams in our way. I think if you went in the locker room you'll see a team that's happy, but they won't be truly happy unless we win it all," the coach said.

"We're not going to get ahead of ourselves. We're not going to think past this next round. Obviously, we have to get to the championship in order to raise a trophy, and we've got a difficult team ahead of us in Salt Lake. We'll keep taking it one at a time, but we're getting closer. This team genuinely believes that we have a realistic shot at this. It means a lot, but we're not going to think about what it means until, hopefully, the end."

"It was important mentality-wise. It could be easy to get into that bunker- mode early, but we didn't. It's one thing to say it and another to do it. We're happy we were able to execute," Johnson said of putting Seattle under pressure early. "I thought some of the stuff we played and chances we created in the first half was excellent and we were rewarded with two good goals."

After falling behind to the Galaxy by a 1-0 count after the first leg, RSL rallied for a 2-0 and 2-1 aggregate victory over Los Angeles on Thursday, putting an end to the Galaxy's quest for a third straight title.

Sebastian Velasquez gave RSL the lead on the night 35 minutes into proceedings. The match went into extra time with the aggregate score knotted at 1-1, and Chris Schuler made himself a hero by sliding in to stab home a free kick from Javier Morales in the 102nd minute, giving RSL the result.

After losing to the Galaxy in the West finals in 2011, RSL head coach Jason Kreis lamented the magnitude of the win.

"It's huge," he said. "I think it just builds an incredible amount of momentum for us. An incredible amount of confidence and positivity. To get that goal in the first half, I think was giant for us. It took a big, big monkey off our backs."

"He was massive," Kreis said of Schuler's effort. "Again, a number of balls he stepped in front of from (Landon) Donovan and (Robbie) Keane today. He made physical challenges and completed the first pass. All those little things were huge for us. Once again this game I walk away from it and I say 'I'm really happy that Chris Schuler scored the game winning goal because he deserved it."

The clubs met three times during the regular season with 0-0 and 3-3 draws and a 4-2 RSL victory at Rio Tinto on Aug. 30.