The second and third best records in the West ground out a chippy 0-0 draw on the Fourth of July in Utah.
Searching for a shakeup, RSL handed debuts to Kenny Mansally and Kwame Watson-Siriboe in defense. Mansally was named man of the match in the shutout.
Salt Lake held 65 percent of possession and passed nearly twice as many as Seattle (484 to 245).
Fabian Espindola picked up a yellow in the 86th minute which will rule him out of this weekend's game against the Portland Timbers. It was the game's fifth booking.
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