MLS Cup will be a rematch of the 2011 edition.
After opening the Western Conference finals with a three-goal victory in the first leg, the Los Angeles Galaxy advanced to Major League Soccer's championship match with a 4-2 aggregate win, falling to Seattle Sounders FC 2-1 at CenturyLink Field on Sunday.
Los Angeles will face the Houston Dynamo in MLS Cup after the Eastern Conference side cruised to a 4-2 aggregate win over D.C. United.
The Galaxy, by virtue of finishing the regular season with more points than the Dynamo, will host the title match at The Home Depot Center, mirroring last season's MLS Cup clash when Bruce Arena's side came out on top in a 1-0 affair in California.
Seattle was in dire need of goals on Sunday and made a bright start when Eddie Johnson latched on to Zach Scott's through ball in the 12th minute, held off Galaxy defender Omar Gonzalez and slipped a shot past Josh Saunders.
The Sounders dictated play for the remainder of the first half but were unable to grab a second goal until the 57th minute. Scott got on the end of Christian Tiffert's inch-perfect corner kick, beating Edson Buddle to the ball at the near post and powering his header to the far side of the net.
Seattle looked poised to get on level terms on the aggregate until referee Mark Geiger awarded visiting Los Angeles a penalty kick in the 68th minute. Robbie Keane's attempted cross was blocked by the outstretched arm of Adam Johansson, and the Ireland international calmly converted the ensuing kick from the spot.
With the Sounders needing two goals to simply force overtime, the experienced Galaxy side closed out the match despite the odd half-chance from Seattle.
Los Angeles and Houston will meet for the title on December 1.