Orlando City captain Kaka scored in his long-awaited return, while reigning MLS champion Seattle Sounders rallied from three goals down to earn a draw against the New England Revolution.
Back on the pitch following a hamstring injury suffered on the opening weekend of the season, Kaka made an immediate impact as high-flying Orlando accounted for the Colorado Rapids 2-0 on Saturday.
After Carlos Rivas broke the deadlock in the 70th minute, former AC Milan and Real Madrid star Kaka came off the bench to seal Orlando's fifth successive home victory in the first minute of stoppage time.
Kaka was on hand to tuck away the rebound from inside the six-yard box after Cyle Larin's strike hit the post.
Orlando is top of the Eastern Conference, two points clear of the New York Red Bulls, who overcame Bastian Schweinsteiger's Chicago Fire 2-1 thanks to goals from Bradley Wright-Phillips and Kemar Lawrence.
Seattle completed a stunning second-half comeback to earn a 3-3 draw with New England.
Trailing 3-0 in the 75th minute, the Sounders rallied through Nicolas Lodeiro before Will Bruin equalised five minutes from time.
Osvaldo Alonso scored the winner with two minutes remaining at home to the Revolution, who played out their third consecutive draw.
It was a five-goal thriller in Columbus as Jack Harrison's brace lifted New York City past the Crew 3-2.
Yangel Herrera – on loan from parent club Manchester City – also scored for New York, which trailed 2-1 early in the second half.
Sporting Kansas City eased past Real Salt Lake 3-0, the Montreal Impact lost 2-1 at home to the Vancouver Whitecaps, FC Dallas and the Portland Timbers drew 2-2, the San Jose Earthquakes edged Minnesota United 1-0 and the LA Galaxy played out a goalless draw against the Philadelphia Union.