Jonathan Lewis struck at the death as New York City FC trumped the New England Revolution, while the reigning MLS Cup champion Seattle Sounders converted a last-gasp penalty against Minnesota United.
Lewis scored in the fourth minute of stoppage time to give host NYCFC a last-gasp 2-1 victory on Sunday.
NYCFC was forced to come from behind against the visiting Revolution, who took a 57th-minute lead through Teal Bunbury.
But NYCFC was back on level terms 20 minutes later when Golden Boot leader David Villa took his tally to 19.
The former Spain international was on hand to fire the ball home from just outside of the 6-yard box.
Lewis then riffled his shot into the back of the net to give NYCFC its third consecutive victory, enough to keep the club second in the Eastern Conference and four points adrift of leader Toronto FC.
The Revolution, meanwhile, are second from bottom in the East and seven points adrift of the playoff places.
There was also a dramatic finish in Seattle as the Sounders defeated Minnesota 2-1 at CenturyLink Field.
Ethan Finlay put Minnesota ahead in the 21st minute, but Chad Marshall replied for the visitors just past the half-hour mark.
But Clint Dempsey scored a 94th-minute penalty as Seattle extended its unbeaten streak in MLS to nine matches.
Expansion franchise Minnesota, meanwhile, is yet to win away from home this season — a run of 10 games.