A header from the defender settled the tie as the home side earned a much-needed victory.
The Galaxy welcomed back starting goalkeeper Josh Saunders, who made his first start since April 21. Saunders had been in the league's Substance Abuse and Behavioral Health program dealing with stress.
Landon Donovan had the best chance of the first half, when his shot from distance rocketed off the post.
In the 61st minute, the home side broke the deadlock. David Beckham swung a corner kick to the back post, which Dunivant nodded home. Timbers goalkeeper Troy Perkins protested to the referee, saying he was impeded by Donovan, but to no avail.
With the result, the Galaxy climbed out of the Western Conference basement. passing the Timbers and FC Dallas.
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