The injury gave Michael Vick his first chance to play meaningful minutes in four years.
Kolb, making his third career start, was looked at by trainers for several minutes on the Eagles sideline. He returned to the game for one more series and threw three short incomplete passes.
Kolb was 5 for 10 for 24 yards and was sacked twice.
Kolb was one of several Eagles injured in the game. Linebacker Stewart Bradley also suffered a concussion -- and also returned to play after his collision.
Left tackle Jason Peters sprained his right knee, yet stayed in the game.
Kolb was making his ballyhooed debut after McNabb's April trade to NFC East rival Washington. Kolb started two games last year after McNabb got hurt in the opener. He put up impressive numbers, becoming the first player in league history to throw for 300 yards in his first two starts.
Kolb struggled all half, even throwing an interception that was overturned by replay.
If he can't return next week at Detroit, Vick played at times like an able replacement. He showed off his former dazzling form on a 31-yard run that led to LeSean McCoy's 12-yard TD run.
Philadelphia's injuries piled up early.
Bradley was hurt when his head slammed into teammate Ernie Sims. Bradley struggled to get up, stumbled, then toppled to the ground. Like Kolb, he returned to play with a head injury before leaving for good.
Weaver suffered a torn ACL on on a rushing play early in the second quarter. His knee was severely twisted on a direct hit and he was down for several minutes. Coach Andy Reid came to Weaver's side and the fullback was helped off the field by teammates and the training staff.
Jackson, who tore a left knee ligament at the end of last season, suffered a torn biceps in his right arm.
The Associated Press contributed to this report.