Real Salt Lake showed no mercy as they shocked high-flying Philadelphia Union 4-0 in MLS, while Jozy Altidore's stunner inspired Toronto.
Jefferson Savarino guided RSL with a brace and an assist to upstage visiting Eastern Conference leaders Philadelphia on Saturday.
Savarino latched onto an Aaron Herrera ball to open the scoring in the 23rd minute and the Venezuela international doubled the lead with 19 minutes remaining at Rio Tinto Stadium.
After Savarino rifled home a second, Albert Rusnak and Damir Kreilach completed the rout inside the final nine minutes of regulation.
The result left Philadelphia with just one win from five games and four points clear of DC United in the east, while RSL are sixth in the Western Conference.
Altidore's memorable 95th-minute free-kick saw Toronto past Canadian rivals Montreal Impact 2-0 away from home.
United States international Altidore curled a set-piece beyond Impact goalkeeper Evan Bush in Montreal following Alejandro Pozuelo's 61st-minute opener.
Columbus Crew fell to their fifth consecutive defeat and eighth straight game without a win after losing 1-0 to Orlando City, while lowly FC Cincinnati made it back-to-back victories by upstaging Chicago Fire 2-1.
Elsewhere, Mason Toye converted a stoppage-time penalty to lift Minnesota United to a 1-0 win after Reto Ziegler missed a 98th-minute spot-kick for Dallas, Sporting Kansas City accounted for Vancouver Whitecaps 3-0 and Portland Timbers drew 2-2 with Colorado Rapids.