As the Seattle Sounders prepare for the second leg of their Western Conference Championship series with the Colorado Rapids on Sunday in Commerce City, Colo. (1 p.m. PT; ESPN, 770 KTTH, El Rey 1360AM), here is a breakdown of the aggregate rules and how the Sounders can advance after beating the Rapids 2-1 on Tuesday night.
The conference championships in the Audi 2016 MLS Cup Playoffs are home-and-home two-leg series based on aggregate scoring.
Each team plays at home once, and whichever team has more combined goals at the end of the two-game series advances. If the score is tied after the two matches, the first tiebreaker is away goals. If the teams have the same amount of away goals, then they will play extra time in the second leg and will go to penalty kicks if the score is still tied.
So what does that mean for the Sounders?
The Sounders will advance with a win or a draw by any scoreline. The Rapids can advance with a 1-0 win or any win by a margin of more than one goal. If the Rapids win 2-1 in the second leg, the match will go to extra time.
Here's what that looks like in chart form: