All three matches Wednesday ended 1-0 in favor of the hosts, with the Seattle Sounders, Portland Timbers and LA Galaxy triumphing.
The Seattle Sounders jumped to the top of the MLS Western Conference after edging Colorado Rapids 1-0 on Wednesday.
Marco Pappa was the hero for the Sounders at CenturyLink Field on Wednesday, with his 16th-minute strike enough to give the home team a 1-0 win.
Pappa controlled the ball outside the penalty box, cut inside his opponent and curled his effort into the top corner of the net, leaving Rapids goalkeeper Clint Irwin helpless.
The result sent the Sounders to first in the West after 12 matches, two points clear of FC Dallas, while the Rapids remain rooted to the foot of the table.