Yordy Reyna scored in the 18th minute as the host Vancouver Whitecaps FC posted a 1-0 victory over D.C. United on Saturday.
Maxime Crepeau made two saves as Vancouver (6-12-9, 27 points) improved to 2-1-1 in its last four matches.
Bill Hamid finished with one save for D.C. United (10-8-9, 39 points), which was unsuccessful in its bid to record back-to-back wins for the first time since May 4 and 12.
D.C. United captain Wayne Rooney quickly made his presence felt in his return from a one-match absence due to what the club called an upper respiratory ailment.
Rooney set up Paul Arriola for a quality chance in the second minute before sending a cross to Steven Birnbaum, whose header sailed over the left corner of the net in the sixth.
The Whitecaps weathered the early storm by D.C. United before Russell Teibert scooted up the middle of the pitch before making a short pass to Reyna. The 25-year-old Reyna unleashed a right-footed shot from outside the box that bounced past Hamid for his fifth goal of the season.
Vancouver barely had time to celebrate its goal before D.C. United nearly answered mere seconds later. Ulises Segura's right-footed shot from the center of the box was denied by a kick save from Crepeau.
The Whitecaps nearly doubled their advantage in the 34th minute, but Ali Adnan's shot from the left side of the box sailed just wide of the right post.
Hamid extended his right arm to make a stellar save in the 59th minute to keep D.C. United within one. The sequence began after Fredy Montero's cross found Derek Cornelius, who unleashed a header from point-blank range.
Reyna's bid for a brace was denied in the 60th minute after his shot caromed off the crossbar.