The MLS reigning champ got back in the win column for the first time since April as Robbie Keane returned from injury.
The Los Angeles Galaxy's winless run in MLS came to an end on Friday, while Jason Johnson scored on the final play to clinch a 2-2 draw for the Chicago Fire.
The Galaxy had not won in five games and looked set for a sixth match without victory against Houston Dynamo until second-half stoppage time.
Alan Gordon's header looped into the net from the cross of fellow substitute Robbie Keane in the 92nd minute, as the Galaxy triumphed 1-0.