If the Portland Timbers advance to Major League Soccer's Western Conference final, they will have earned it.

The Timbers will be playing their third playoff game in nine days Thursday night when they travel to Seattle for the second leg of their semifinal series. Portland beat host FC Dallas 2-1 in a elimination-round match on Oct. 31, then won the opener of their semifinal series against the Sounders 2-1 on Sunday at home.

The second leg normally would have been played this weekend, but a car show at CenturyLink Field forced the game to be moved up.

"It definitely changes things because you have to think about different components, different than if you had to play weekend after weekend," Timbers coach Giovanni Savarese told The Oregonian. "This is what has been thrown at us. This is what we have in hand. We have to go forward and deal with it and make sure we make the best out of it."

The Sounders gained an all-important road goal in the first leg but might have lost a lot more.

Defender Chad Marshall and midfielder Cristian Roldan were both forced to exit the Sunday match with first-half injuries.

Marshall, the only three-time MLS Defender of the Year and a finalist this season, underwent surgery Tuesday for a torn meniscus in his right knee. He will miss the Thursday game.

Roldan, who became the first Sounder to start all 34 games and played in all but seven minutes in the regular season, is listed as day-to-day with a hip flexor injury.

Still, the Sounders have that away goal, the first tiebreaker should the teams finish the second leg even.

"We're not out," Seattle goalkeeper Stefan Frei said. "I won't even call this a setback. A setback would be if we were down 3-0 and going home. That sucks. We're in this. We got an away goal, we're confident in our play at home, and we believe we have a better team than them."

While the Sounders will scramble to make changes to their starting lineup, the Timbers will get back defender Larrys Mabiala, who was suspended for the first leg after receiving a red card in a the playoff opener at FC Dallas.

Raul Ruidiaz gave the Sounders a 1-0 lead in the first leg with his 11th goal in 14 starts since joining the team at midseason, but Jeremy Ebobisse and Sebastian Blanco answered for the Timbers in the opening half-hour.

"It was important to win at home in front of our fans and get a slight advantage heading into Seattle because everyone knows how difficult it is to get a result up there," Ebobisse said.

While the Cascadia Cup rivalry dates back to 1975 in the old North American Soccer League, the Sounders are 10-10-6 all-time against the Timbers in MLS regular-season and postseason play, including a 7-2-3 at home.

--Field Level Media

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