New England coach Brad Friedel insisted his team would give its best effort in the season finale Sunday against Montreal, which needed a victory to keep its playoff hopes alive.
Midfielder Diego Fagundez and goalkeeper Matt Turner made sure Friedel kept his word.
Fagundez scored an unassisted goal in the 74th minute and Turner made four saves as the host Revolution ruined the Impact's playoff bid with a 1-0 victory in Foxborough, Mass.
New England (10-13-11, 41 points) won for just the second time in its final seven matches.
Montreal (14-16-4, 46 points) entered "decision day" two points behind sixth-place Columbus in the race for the Eastern Conference's sixth and final postseason berth.
The Impact needed a victory in New England and a loss or tie by the Crew to make the playoffs.
But New England made that moot with the victory as the Columbus game was delayed by a lightning storm. The Crew wound up beating Minnesota United 3-2.
Fagundez got the winner, taking a pass that deflected off a Montreal defender at the top of the 18-yard box and firing a right-footed shot into the lower left corner past diving goalkeeper Evan Bush.
After a scoreless first half, the Impact pressed hard for a goal early in the second half.
Turner made a stop on a Quincy Amarikwa shot that was headed for the lower left corner in the 50th minute.
Montreal's Alejandro Silva took a pass near the top of the 18-yard box in the 54th minute, spun and took a left-footed shot that Turner was forced to save with a diving stop to his left.
The Revolution's Kelyn Rowe nearly caught Bush out of the net on a shot from just over midfield in the 50th minute, but his long chip went just over the crossbar and settled in the top netting.
New England's Teal Bunbury had the best chance of the first half, but his shot from just outside the 18-yard box was saved by Bush.
Bush was forced to make two saves in the first half, while Turner made one.