Bears outside linebacker Lamarr Houston suffered a season-ending anterior cruciate ligament tear in his left knee and nose tackle Eddie Goldman is expected to miss at least four weeks with a high left ankle sprain, sources told the Tribune.
The Bears won't set a firm timeline for Goldman's return but are targeting the Oct. 20 game in Green Bay.
Meanwhile, defensive backs Adrian Amos and Bryce Callahan remain in the concussion protocol, and backup safety Chris Prosinski has a bruised calf.
If you're keeping track, that's significant injury problems across all three levels of the defense. The Bears already were thin at safety, outside linebacker and defensive tackle.
Coach John Fox was asked Tuesday if the latest wave of injuries had him shaken.
"Not really," he said. "I've always been of the belief that tough times don't last, tough people do. And injuries are a part of that."