Portland Timbers forward Frederic Piquionne right, battles for the ball with Real Salt Lake defender Chris Schuler in the first half of the second game of the Western Conference finals in the MLS Cup soccer playoffs Sunday, Nov. 24, 2013, in Portland, Ore. (AP Photo/Don Ryan)

PORTLAND, Ore. - Long after all the fans had gone and the turf was being vacuumed of confetti, Real Salt Lake was still celebrating its Western Conference championship.

Aided by a boom box, RSL players sang and danced as they headed for their bus following Sunday night's 1-0 victory over the Portland Timbers. The win gave Salt Lake a 5-2 aggregate advantage in the two-leg conference final.

It also gave the team a spot in the MLS Cup against Sporting Kansas City on Dec. 7.

"It's a good win for the team," said Robbie Findley, who scored the only goal in the second leg. "I think everybody put in the hard work, and when you have that, when you have all the guys committed to working hard and doing their jobs, you win games. We feel good right now, but we have one more to go."

Salt Lake, which won the league championship in 2009, took a 4-2 lead two weeks ago at Rio Tinto Stadium in the first game of the conference final.

Salt Lake has been to the playoffs for six straight seasons, the longest active streak in MLS. It lost to Seattle in the conference semifinals last season.

RSL advanced to this year's conference final by eliminating the two-time defending league champion Galaxy in the semis.

Sunday's victory extended RSL's unbeaten streak against Portland to 10 straight matches. The Timbers remain winless against Real Salt Lake since their first meeting when Portland joined MLS in the 2011 season.

Portland went into the match with just one home loss this season. The Timbers were looking to become the first team in nine years to come back from a two-goal shortfall in the second match of an aggregate-goals series.

Portland appeared to score off a corner in the 15th minute but the goal was waived off by the referee because of a foul in the box, frustrating the sellout crowd at Jeld-Wen Field.

Findley had a rebound goal in the 29th minute. The RSL reserves spilled off the bench to join the celebration on the sideline, while Timbers first-year coach Caleb Porter looked on with pursed lips.

Portland had a second goal nullified in the 33rd minute when Futty Danso was called offside by the linesman.

"If Portland scores the first goal, they have all the momentum, they're on their home field, they've got their fans behind them and I think we would have been in a really, really tough place," RSL coach Jason Kreis said. "If we score the first goal, now it's three goals, now they get a little desperate, some heads are hanging and there's some frustration involved. So great that we got the goal. Probably wasn't the prettiest one we've ever scored, but we'll take it and I thought we handled the match well from there."

Porter said the officiating wasn't to blame, but he couldn't understand why the Timbers' first goal was called back. He called it a "phantom foul."

"I'm left scratching my head as to what he saw on that play," Porter said.

The Timbers outshot Real Salt Lake 18-7 for the match.

"You could see their maturity, you could see their experience," Porter said about Salt Lake. "And they did what they needed to do."

Salt Lake was without striker Alvaro Saborio, the team's leading scorer with 12 goals this season, because of a right hip flexor injury that also kept him out of the first leg. He did not travel to Portland. Salt Lake defender Chris Wingert was also out because of a broken rib and collapsed lung from the first leg.

Meanwhile, Portland's top scorer, Diego Valeri, had struggled with an adductor injury, but practiced at full speed this week and started.

Sporting advanced to the final with a 2-1 victory over Houston in the second leg of the Eastern Conference final on Saturday. The teams played to a scoreless draw in the first match.

It's Sporting's first trip to the MLS Cup since 2004.

The Timbers finished last season 8-10-16 for eighth place in the conference and 17th in the league. But they made a dramatic turnaround under Porter, finishing atop the conference for their first playoff appearance.

News from © The Associated Press, 2013