Discipline and trust are two words often heard in discussions of the problems and growing pains faced by a Bears defense that has had to replace seven starters.
Four starters are on injured reserve -- including Charles Tillman, who is designated for return, although that wouldn't happen until the postseason. Lance Briggs will miss his fifth straight start Sunday, Stephen Paea has already missed three games and Shea McClellin missed two.
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In filling those gaps, the Bears' defense has become younger and less experienced. Teaching players, especially young players, the discipline to consistently adhere to their assignments and to trust that their teammates will do the same is a challenge.
"That's part of raising young players to be the players you want them to be," said Bears coach Marc Trestman. "What we're trying to convince them to do is not worry about anybody else. They're probably not at a stage where they see the big picture because that takes time."
Step one is teaching players their specific roles and how that affects the overall scheme of the defense.
"(It's) just learning what they do in the framework of their telephone booth (area) and focusing in with blinders on (reading) their specific key that's going to take them to the right spot," Trestman said. "The flipside is the veteran player who has a big picture and knows that this guy (next to him) is going to need some help.
That causes some veteran players to try to do too much.
"He's thinking, 'How can I help (the guy next to him)?'" Trestman said. "And then he goes outside the parameters of his job. That's the discipline that we're trying to work on. There have been moments over the last three or four weeks that we've had that (discipline), and there have been moments certainly as we all know that we haven't. That's the challenge week to week."
Help on the way:
After a full practice on Friday, tackle Jeremiah Ratliff is expected to provide some much-needed help on the defensive line Sunday.
But the four-time Pro Bowl pick hasn't played in a year after off-season groin muscle surgery, and he will be limited to a set number of snaps. That number will be determined and monitored by coach Marc Trestman, defensive coordinator Mel Tucker, defensive line coach Mike Phair and team trainers.
Trestman expects the 6-foot-4, 303-pound nine-year veteran to see time at nose tackle and the 3-technique and to make an impact despite his recent inactivity.
"He's brought something to our locker room already," Trestman said. "And on the practice field, our offensive linemen have felt his presence on the field during the week. That's a good sign.
"We're not going to make any proclamations at this point in time. But demeanor-wise, his attitude, the way he's fit into our locker room and the way he practiced this week, he was a guy that everybody realized was out there practicing. We'll see where it takes us on Sunday."
Safety in numbers:
Starting strong safety Major Wright is questionable, and if he can't go Sunday, veteran Craig Steltz would start in his place.
First-year safety Sean Cattouse was promoted from the practice squad to the active roster as a precaution, and defensive tackle Tracy Robertson was waived.
Steltz has started seven games and played in 72 in his six years, all with the Bears.
"Craig's been around. He knows the position," coach Marc Trestman said. "He knows his assignments. He's not a guy who's going to make a lot of mistakes. I think we'll be fine at the position. I have a lot of comfort with him."
The 6-foot-2, 210-pound Cattouse is a Chicago native who played at Hubbard High School. He entered the NFL with the Chargers in 2012 as an undrafted free agent out of Cal. He has been on the Bears' practice squad the last eight weeks and will continue to wear No. 36.
Defensive tackles Jeremiah Ratliff (groin) and Stephen Paea (toe) are questionable after full practices Friday. Safety Major Wright (hamstring) and cornerback Derrick Martin (hamstring) are also questionable after limited Friday practices. Wright's injury occurred during practice, and he could be a game-time decision.
Running back Matt Forte (knee) and wide receiver Brandon Marshall (quadriceps) had full practices and are probable, as is kicker Robbie Gould, who was sent home with an illness and did not practice. Quarterback Jay Cutler (ankle), linebacker Lance Briggs (shoulder) and safety Anthony Walters (groin) did not practice and are out.
Two Vikings starters, tight end Kyle Rudolph (foot) and cornerback Josh Robinson (chest) are out. All other injured players had full practices and are probable, including running back Adrian Peterson (groin).
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