Bears' backbone still the 'D'

QB switch a factor, but fixing defense remains top issue > Fix the defense and the Bears still can have great Rex-pectations this season with Rex Grossman filling in at quarterback. He could show as much efficiency and explosiveness as Kyle Orton has in successive weeks and still come up short if the Bears don't improve their pass rush and coverage. Orton update: MRI shows no tear, out 3-4 weeks What's Goin' On: Covering the coverage of the Bears RosenBlog: Blair Rex Project scaring pants off Lovie Urlacher angered by fans' booing of Grossman (link)