Sebastien Le Toux scored his 11th league goal of the season in the 36th minute, leading the Philadelphia Union over Chicago 1-0 Saturday and extending the Fire's winless streak to five.
The French-born Le Toux received a green card this year, potentially making him eligible to play for the U.S. national team. The 26-year-old midfielder and forward is third in MLS in goals, trailing Los Angeles' Edson Buddle (13) and New York's Juan Pablo Angel (12).
Le Toux beat goalkeeper Sean Johnson after receiving a pass from Justin Mapp.
Philadelphia (6-11-6) became the last MLS team with a shutout this year. In goalkeeper Brad Knighton's only previous start, he received a red card Aug. 8 at Dallas and was replaced by Chris Seitz.
Chicago (6-8-8) has three losses and two draws in its last five matches.