"We're on the side of caution," GM Jerry Angelo said. "We feel Marcus in good shape and he wants to push this thing. We just want to make sure that he's a 100% back. We don't want any relapses. We'll take our time. Where not lining up next week and we know what Marcus can do, so he doesn't have to come out and prove anything."
Warrick Holdman also had an MRI on Thursday. The knee that caused him to miss time last year has been acting up and he will have his knee scoped sometime next week.
"I think about it as a flushing of the joint," head coach Dick Jauron. " I think he'll be a couple of weeks, but some guys come back quicker and some sooner."
Middle linebacker Brian Urlacher has missed the last two practices with a lower back strain.
"I don't know what happened," Urlacher said. "I got hit with a helmet in the back. I thought it might have been bruised or something. Then I went back after practice and laid down. I got up and I couldn't even walk. My whole upper body was stiff. It freaked me out when I couldn't bend over."
The Bears linebacker core looked like a strength coming into camp, but a eight days later Holdman is out with a knee problem, Urlacher has missed practice time with a lower back strain and Sean Harris retired.
Other injured Bears include Blake Brockermeyer with a left knee problem, Al Wallace also with a left knee injury, Karon Riley left practice with a hip flexor problem and Mike Gandy has a right ankle injury. Brockermeyer said his injury could keep him out a week or so.