The teams atop the Eastern Conference swapped spots in the standings with opposite results on Saturday.
Chicago 4, Vancouver 0
Nemanja Nikolic scored two early goals, pushing his MLS-leading total to 16, and the Chicago Fire beat the Vancouver Whitecaps 4-0 on Saturday night to take the Eastern Conference lead.
The Fire (11-3-4) have won four straight and are 8-0-2 in their last 10.
Arturo Alvarez added an impressive goal early on Matt Polster's second assist, and Michael de Leeuw had an assist and his first goal for Chicago, which tied the club record of eight-straight home wins. The last time Chicago won eight straight at home it spanned two seasons.
Nikolic set the tone early with strong finishes in the 14th and 18th minutes, one of them a scorching one-timer, but Alvarez's finish in the 25th minute was even more impressive. Polster sent a cross that Alvarez volleyed out of the air with his left foot for his second goal of the season.
Matt Lampson made three saves for his sixth shutout, improving to 8-0-2 this season.
Vancouver (6-7-3) had its three-game unbeaten streak snapped.
Roland Lamah scored two goals to lead FC Dallas to a 3-1 victory over Toronto FC on Saturday, knocking the Canadian club out of first place in the Eastern Conference.
Maximiliano Urruti added a goal and an assist for Dallas (7-3-7). Dallas continued its home dominance of Toronto, having never lost in nine meetings.
Toronto (10-3-5) dropped into second place behind Chicago, a 4-0 winner over Vancouver on Saturday.
Lamah, who has six goals in the first MLS season, took a short pass from the left side by Urruti for a close-in goal in the fifth minute. Lamah made it 2-0 in the 21st off a through ball from Mauro Diaz.
After Toronto cut the deficit in the 56th on Marco Delgado's tap-in off a deflection, Urruti took a through ball and easily beating goalkeeper Alexander Bono in the 78th for his 10th goal of the season.
Blerim Dzemaili scored and set up defender Chris Duval's goal in a two-minute span in the first half to help the Montreal Impact beat D.C. United 2-0 on Saturday night.
The Impact (5-5-6) snapped a five-game winless streak in all competitions. D.C. United (5-10-3) slipped into last place in the Eastern Conference.
Dzemaili opened the scoring in the 21st minute. He got the ball in midfield after a quick goal kick by Evan Bush. The designated player wasn't challenged as he dribbled toward the goal before firing a side-footed shot past the outstretched Travis Worra in net.
Dzemaili was at it again in the 23rd. From a similar spot from where he scored, Dzemaili faked a shot and chipped it to Duvall, who slid in the box and gently tapped the ball into the bottom corner.
COMMERCE CITY, Colo. (AP) — Marlon Hairston scored twice, Kevin Doyle had a goal and an assist and the Colorado Rapids beat the Houston Dynamo 3-1 on Saturday night.
Dominique Badji had a role in all three goals for the Rapids (6-3-1). They came in with the fewest points in the MLS, but kept the Dynamo (7-7-4) winless in nine road games this season (0-7-2).
Doyle scored into the corner of the net off a short cross from Dillon Serna for his fourth goal this season in the 21st minute. Colorado goalkeeper Tim Howard made two great saves just before Houston broke through in the final minute of first-half stoppage time on Erick Torres' 12th goal.
Hairston broke the tie, tapping in a short cross from Badji, who beat a defender and the goalie to the ball near the goal line in the 48th. Hairston added his second goal and third of the season in the 69th off passes from Badji and Doyle.
KANSAS CITY, Kan. (AP) — Daniel Salloi scored his first career MLS goal in the second half and Sporting Kansas City tied Portland to remain unbeaten at home.
Salloi took a delivery from Roger Espinoza, settled the ball and found the top corner in the 60th minute. Sporting KC (8-4-7) leads the Western Conference and is 6-0-3 at home.
Diego Valeri scored his 10th goal in the 26th minute for the Timbers (7-7-5).
COLUMBUS, Ohio (AP) — Hector Villalba scored twice, Alec Kann had an assist and earned his fourth shutout and expansion Atlanta beat Columbus.
Atlanta struck in the 27th minute when the Crew defense didn't get a touch on Kann's goal kick, and Villaba beat goalkeeper Zach Steffen to the ball. Villalba picked up his eighth goal in the 64th minute when a deflection to the middle of the box ended up on his foot and he rolled the ball between a defender's legs passed the shielded Steffen. Villalba immediately left the game with cramps.
Altanta (8-7-2) moved past Columbus (8-10-1) for fifth in the Eastern Conference.