Brian Ching came off the bench to score what he thought was the winner, but the stoppage-time strike was ruled offside.
Houston opened the scoring a minute before halftime. Corey Ashe fed Calen Carr down the inside left channel. Carr did a stepover to separate from Alessandro Nesta and cut the ball toward the center of the box, where Will Bruin tipped in in deftly for his 12th goal of the season.
The Impact equalizer came after the hour mark. Marco Di Vaio found Sanna Nyassi, whose first touch took him past Bobby Boswell. Nyassi pushed the first attempt straight at Tally Hall, but cleaned up the rebound.
With 20 minutes remaining, the Dynamo chucked Brian Ching into the fray. Before this season, Montreal selected Ching in the Expansion Draft, exasperating Ching, who wanted to retire in Houston. The Dynamo had to trade a draft pick to reacquire the U.S. international striker.
Ching quickly made his presence felt. He picked out Cam Weaver, whose hasty one-time shot clopped off the post. Soon after, Ching had a close shot blocked on the line by Troy Perkins.
The game built to a frenzy. Impact coach Jesse Marsch was ejected for protesting the lack of a penalty call for his team. Then, in the third minute of stoppage time, Brian Ching latched onto a long ball and delicately chipped the goalkeeper for what he thought was the winner. The referee, however, thought differently. A touch by Weaver meant Ching was offside, and the official nixed the goal.
The result officially eliminated Montreal from playoff contention.
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