BOURBONNAIS (MCT) -- After missing two weeks of training camp and being gone for a week for personal reasons, Chicago Bears middle linebacker Brian Urlacher has undergone arthroscopic surgery on his left knee.

An NFL source told the Tribune Urlacher underwent the procedure Tuesday, 26 days before the start of the regular season. The Bears and Urlacher have maintained all along that he will be ready to play against the Indianapolis Colts Sept. 9 at Soldier Field. It is unknown at this point if today's surgery will alter that timeline.

Urlacher was asked in an interview on Monday with WFLD Fox-32 if he had arthroscopic surgery during the time he was away from training camp at Olivet Nazarene University last week.