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.
(Copyright 2010 Philadelphia Union. Reprinted by permission)