Robbie Findley's first-half goal put a comeback out of reach for the Timbers and Real Salt Lake advanced to the MLS Cup with a 1-0 victory over Portland on Sunday night for a 5-2 aggregate advantage in the Western Conference final.

Salt Lake took a 4-2 lead two weeks ago at Rio Tinto Stadium in the opener of the two-leg series. RSL, which won the league championship in 2009, will play Sporting Kansas City for this season's title on Dec. 7.

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 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.

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

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 the Houston Dynamo 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. Houston, the runner-up in 2011 and 2012, will miss the title game for the first time in three years.

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 their first-year coach, finishing atop the conference for their first playoff appearance.

Salt Lake has been to the playoffs for six straight seasons, the longest active streak in MLS. Last season the team fell in the conference semifinals to the Seattle Sounders. RSL defeated the two-time defending league champion Galaxy in the conference semifinals to advance this season.