Bottom of the table Montreal took all three points from top of the table New England.
Marco Di Vaio's pass found Andrés Romero in the very early going and the Argentine's finsh had the home side on top inside the first five minute of the game, giving the Revolution an early warning of the potential for an upset.
A bit of poaching from Jack McInerney made it 2-0 before the break. The striker pounced on a rebound and banged it home.
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Had it not been for a last-ditch tackle from A.J. Soares, Di Vaio would have made it three before the half. The New England defender played the Montreal star on side before tracking back and blocking a shot that otherwise was headed for an open goal.
Despite New England's scoring form of late, and one really good shout for a penalty, the Revs could not cut the lead as they bombed forward in the second half, and Montreal held on to its halftime lead. The game marked the first time New England has not scored since April, and the team's first loss seven matches.