As the first four games of the season have illustrated, the Galaxy have not been on their best form. There is an argument that all the injuries have limited the scope of their attack, and Bruce Arena has yet to work out their best formation.
Indeed, the Galaxy again will be without captain Robbie Keane, who underwent knee surgery, and Giovani Dos Santos will likely be a game-time decision after resuming full training last week.
But injuries haven't seemed to have disrupted their home form. The Galaxy are always abnormally difficult to beat at StubHub Center and wins against D.C. United and the San Jose Earthquakes have set the early season tone to what you would imagine Bruce Arena hopes will be the regular.
The Portland Timbers, however, spoiled the house party last season with that famous 5-2 victory in October. The win seemed to have strengthened Caleb Porter's side, as they carried all the momentum into the playoffs.
Obviously, the latter has to be put into the context of lat season. The Timbers are currently winless in their last three games, last losing 4-1 to a Kaka-inspired Orlando City.
Even before the ball rolls on Sunday, the Galaxy will know earning points at home is always a must. With little to look back on in their first two road games, the Galaxy can't afford too many slip-ups at home. The wonder now is where the goals will come from.
LA Galaxy 2-5 Portland Timbers - October 18, 2015 - MLS
The Timbers came from a goal down to record a stunning 5-2 victory over the Galaxy at StubHub Center. The win was the start of an impressive late in the season run that finished with the Timbers lifting their first MLS Cup.
LA Galaxy (4-4-2): Kennedy; Rogers, Steres, Van Damme, Cole; Dos Santos, De Jong, Husidic, Zardes; Magee, Lletget
Portland Timbers FC (4-3-3): Kwarasey; Powell, Borchers, Taylor, Barmby; Valeri, Chara, Nagbe; Melano, Adi, Asprilla