The majority of the expected 40,000 fans at the neutral venue will be supporters of local team Seattle Sounders and are unlikely to support the Galaxy against underdogs Salt Lake.
"I don't think the Sounders (fans) like them at all, I think they are going to be on our side," Salt Lake midfielder Andy Williams said.
Captain Kyle Beckerman shared that hope and expected a passionate atmosphere in a stadium that has hosted the biggest crowds in the league this season.
"It was amazing the time we came and played the Sounders," Beckerman said. "It has been great to watch any game they have had on television.
"The fans really support their team well here. It has a real European atmosphere (and) I'm hoping it will be something like that on Sunday. Hopefully all the Sounders fans will get on our side for the game".
Given their regular season record of just two away wins, Salt Lake would prefer to have at least the feeling of home advantage.
As well as the crowd, another factor that may make Salt Lake feel at home is the artificial playing surface.
Until they moved to their own stadium at the end of last season, the team played at the University of Utah's Rice-Eccles American football stadium, which had an artificial surface.
"It definitely has a fast feel to it here but a lot of us actually have some experience on it from Rice-Eccles back in Salt Lake and we did pretty well on it last year so hopefully we can take some of that and bring it here," he said.
Much of the focus had been on the more high-profile Galaxy, which had clearly irked the Salt Lake side and Beckerman showed that when talk turned to the likes of Donovan and Beckham.
"We came here to win. We think we can win," he said.
"We don't really care who we're playing, who is on the team. It should be fun."
