A second-half Marco Pappa goal helped the Chicago Fire to their third straight MLS win, a 1-0 victory over Sporting Kansas City on Friday.
The Fire closed to within two points of the third-placed Kansas City in the Eastern Conference with the hard-fought win at Livestrong Sporting Park.
Sporting enjoyed the majority of possession in the first half but struggled to create any clear-cut chances.
They were made to pay in the 58th minute when Chicago struck on the counter-attack.
Pappa carried the ball over halfway before sliding a pass to Chris Rolfe, who returned a pass for the Guatemalan to strike a first-time shot past goalkeeper Jimmy Nielsen.
Sporting had their best chance 14 minutes before full-time when Kei Kamara had a diving header turned around the post by Fire shot-stopper Sean Johnson.
Johnson was called into action several times in the closing stages but stood up to the tests as the Fire held on to collect three points.