"[We'll miss Urlacher] in all phases," Lovie Smith said. "Great player. He's one of the leaders. He makes all of the calls. Just him being in the huddle helps. We're going to miss him. I can't belittle that at all. We're missing a great player. But you just have to look at Plan B. Plan B for us is pretty good if you do lose a guy like that."
Urlacher and Lance Briggs, who have a combined 15 Pro Bowl appearances, have started 180 games together since Briggs' rookie season in 2003. It will be the first time Briggs has played without Urlacher since 2009, yet Briggs said it won't change how he plays on the field.
"No. Just play. Play your game. Do what you do best," said Briggs.
Briggs' responsibilities won't change, as he'll stay on the weak side. Yet Nick Roach, who has started the past 28 games for the Bears at strong side, or Sam, linebacker, will have entirely new set of duties filling in for Urlacher.
LB Nick Roach
Rob Grabowski/USA TODAY Sports
"I wish that Brian was in there, obviously. It's unfortunate to see him go down," said Roach. "But I've been prepared for [the switch] for a while."
Roach has started 55 games in his six-year career but only three of those at the middle linebacker, or Mike, position, where he'll now be in charge of making the calls on the field.
"On the outside you really don't have to begin any of the communications," Roach said. "Playing in the middle you have to be the one to initiate all the checks and start all the adjustments. It starts with the Mike letting everybody know something is going to change once we get set, or just in general getting the call to the defense, and everybody else's job is just to echo."
Briggs said the experience of the defense together will make Roach's job as traffic cop much easier.
"Communication is not going to be a problem," said Briggs. "Even if guys don't hear, we've been in the system long enough where we understand, we should all understand, by recognizing formation and seeing what [sets] teams are in."
Playing inside also changes Roach's gap responsibility against the run, which will be crucial this week when Chicago faces arguably the best running back in the game in Minnesota's Adrian Peterson.
"It will be different just because I'll be in different spots," Roach said. "We have different gaps depending on which linebacker spot that you're lined up in. So the different types of tackles that you would be able to make at Sam won't come up at Mike because you're in a different position. In terms of stopping [Peterson], you've still got to get everybody to him to get him down."
Replacing Roach on the strong side will be Geno Hayes, whom the Bears signed this past offseason. He played his first four years in the league in Tampa Bay's version of the Cover 2 defense. Hayes spent the entire preseason in the starting lineup next to Roach and Briggs, while Urlacher was recovering from knee surgery.
"This is not my first time around. It's not my first rodeo," Hayes said. "It was great getting good experience in the preseason, getting accustomed to the defense, accustomed with the guys. I was out there playing ball day in and day out. So, it was great."
The opportunity for Hayes to get first-team reps in the preseason, learning on the fly his responsibilities alongside Briggs and Roach, should make it an easy transition for him come Sunday afternoon at the Metrodome.
"It helps plugging Geno in because coaches have seen what he can do, not only just here in training camp but what he did in Tampa Bay," said Briggs. "He's a very good linebacker. And this is a great opportunity for him."
LB Geno Hayes
Hayes was signed to a one-year deal this offseason. The next four games will be his chance to prove he deserves a long-term deal.
"It's a great opportunity," Hayes said. "Any time you get the opportunity to step on the field and make plays, it's always that chance you've got to go out there and take. It's big."
No one can replace Urlacher but Hayes believes, as a group, the current linebacker trio is good enough to help guide the Bears into the playoffs.
"Yes, we can," said Hayes. "We have guys in position. Nick is going to be a great guy. He can step in to that role and make those plays that we need to make at middle linebacker, so we're not really worried about that. We're going to still have Urlacher on the sideline giving us tips and things of that nature, so we're not too worried. We're going to do what we came to do."
Briggs said that, if Chicago can make the playoffs this year – which will likely require the team winning three out of its final four games – he expects Urlacher to return in the postseason.
"We're fortunate that Brian went down and we're 8-4 with four games to get into the playoffs," Briggs said. "It's our job now to get ourselves into those playoffs. To make sure we get into the playoffs. Once we get in those playoffs, Brain will be ready, and he'll come back and he'll lead us the way he always has."
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Jeremy Stoltz is Publisher of BearReport.com and a member of the Pro Football Writers of America.