He was ruled out at the beginning of the third quarter. Second-year player Halapoulivaati Vaitai replaced Johnson in the lineup.
The injury puts Johnson's availability for Thursday night's game at the Carolina Panthers in question. If he has a concussion, there would be little time for him to pass the league-mandated protocol.
Since the start of last season, the Eagles are 8-2 with Johnson in the lineup and 2-8 in the 10 games he missed because of suspension.