The New England Revolution claimed a 3-1 win over Sporting Kansas City to further close the gap on their Eastern Conference rivals on Wednesday.
Sporting sit second in the East but have lost their last three games, with the third-placed Revolution on a matching winning run to narrow the difference to six points.
Soony Saad opened the scoring in the ninth minute for Kansas City but an equaliser from Teal Bunbury and two goals from Lee Nguyen turned the game on its head.
A goal from Conor Casey was enough to give the Philadelphia Union a 1-0 win over Toronto FC who saw Ashtone Morgan sent off.
A brace apiece from Obafemi Martins and Andy Rose had the Sounders 4-0 up at the break before a Marco Delgado strike and a Ryan Finley penalty gave the score some respectability.