Seattle (4-1-1, 13 points) ran its unbeaten streak against the Galaxy to 10 games, and became the first MLS team in history with a streak that long against the Galaxy (0-2-3, 3 points).
Morris finished a cross on the run from teammate Leo Chu for his fifth goal in two matches, after Morris scored four for the Sounders in last week's win over Sporting Kansas City. It was his 50th career regular-season goal for Seattle, his 60th goal across all competitions, and he became the first ever Sounders player to record five consecutive goals for his team.
Chu's assist was his fifth in two games, as he had a hand in all five of Morris' goals across the two matches.
Chu scored Seattle's second goal in the 35th minute, and his first of the season, when his defender fell down trying to mark and Chu raced away toward the box with the ball. Nicolas Lodeiro got the loose ball and fed Chu, who had plenty of time and space to shoot.
Chu rolled a shot under the outstretched arm of Galaxy goalkeeper Jonathan Klinsmann, then grabbed an extra ball and put it under his jersey in celebration.
The Galaxy made it interesting by outplaying the Sounders in the second half. Jalen Neal's goal in the 63rd minute came in the midst of a sustained Galaxy possession and pressure that had Seattle hanging on to a precarious lead.
The Galaxy had a couple of good looks on goal in the first half but couldn't finish them. Preston Judd had a great chance when he made a run and had a point blank shot on goal, but Seattle goalie Stefan Frei blocked it for a save.
Neal put in the follow of a shot that Frei couldn't bring in cleanly, standing in the right place to put away the rebound.
The Galaxy had more corner kicks and shots but couldn't find a tying goal before time ran out. Frei was forced to make seven saves, including one big stop on the final play of the match.