Matt Hedges headed home the winner in the 87th minute, and visiting FC Dallas beat the Vancouver Whitecaps 2-1 on Sunday to climb into first place in Major League Soccer's Western Conference.
Maximiliano Urruti sent a corner kick into the box and Michael Barrios flicked on a header at the near post. Hedges attacked the ball at the far post and headed it in to break a 1-1 tie.
FC Dallas jumped over Sporting Kansas City for the top spot in the West.
The defeat was a blow to the Whitecaps' playoff hopes. Eighth-place Vancouver (11-11-7, 40 points) sits four points behind the Seattle Sounders (13-11-5, 44 points) for the West's sixth and final playoff position. The Whitecaps have dropped back-to-back matches after going unbeaten in six straight.
Kei Kamara's goal in the 66th minute had lifted Vancouver into a 1-1 tie.
Kamara out-jumped a defender to head in Alphonso Davies' cross from the left flank. Davies, a 17-year-old Canadian sensation headed for Bayern Munich of the German Bundesliga after the season, triggered the play by dribbling the ball through and around defenders with a burst of speed.
The goal was Kamara's team-leading 13th of the season.
Santiago Mosquera scored in the 42nd minute for Dallas to open the scoring.
Vancouver's ability to perform well in a big game was questioned in days leading up to the contest. However, the Whitecaps did little to quell their critics in the first half, managing no shots on target and only causing two corner kicks.
Davies did force Dallas goalkeeper Jesse Gonzalez to stop a deflected shot in the 33rd minute. Still, the Whitecaps were not overly dangerous otherwise as Dallas enjoyed a slight edge in possession before the break and generated six corner kicks.
Mosquera opened the scoring when he headed Urruti's free kick past Whitecaps goalkeeper Stefan Marinovic.
Vancouver winger Yordy Reyna returned from a one-game suspension for yellow-card accumulation but was held in check most of the game as Dallas denied the Whitecaps many of their trademark counter-attacks.
Whitecaps left back Brett Levis departed after the first half due to a left quadriceps strain. He was replaced by midfielder Nicolas Mezquida as coach Carl Robinson adjusted his formation, going with three defenders.