Updated

Changes? The Chicago Bears defense has made plenty.

Landon Cohen, David Bass, Jonathan Bostic and Zach Minter? They didn't necessarily figure into the team's plans when the season started. They sure do now.

Talk about a game of adjustments.

None of the injuries or shuffling of personnel seems to faze defensive coordinator Mel Tucker or coach Marc Trestman as they try to put a group on the field Sunday against the Washington Redskins. The hope is they can locate some sort of pass rush to hassle quarterback Robert Griffin III and stop the running game.

"It is what it is," said Tucker, who went through his share of injury-riddled defenses in four years as Jacksonville's defensive coordinator. "I think we're all in this thing together. We feel like we have a good group. We feel like we can do what we need to do to perform and play winning football. In terms of the challenge, every day is a challenge regardless of the situation. But that's why we play this game. That's part of it."

The Bears have lost middle linebacker D.J. Williams for the season to a pectoral tendon tear, and Bostic, his replacement, is a rookie. They lost defensive tackle Henry Melton and his replacement, Nate Collins, to knee injuries. They moved defensive end Corey Wootton inside while starting Shea McClellin at end. They've had to deal with starting nose tackle Stephen Paea missing games with a toe injury and cornerback Charles Tillman missing his first start since 2009 with a knee injury.

Players like Bass and Cohen, who weren't even with the team until the regular season, have had to fill in at line spots, while backup cornerback Zack Bowman has had playing time for Tillman.

And although the defense ranks well below its traditional spot under former coach Lovie Smith — 20th overall and 23rd against the pass — coaches see reason for optimism.

"We have a good group of rookies, a nice group," Tucker said. "They know that at some point they are going to be called upon to play for us and have a role. And whatever that role is, it can change. So they are ready for that. It's the next-man-up mentality for us and it's been that way since Day 1 and it hasn't changed."

The Bears weren't always well equipped to handle adversity like this under Trestman's predecessor, but most of those injury problems occurred on the offensive side of the ball. This is different.

Trestman says it's an NFL coach's job to develop young players through fundamental work so they're ready to fill in. He likes what he's seen of the way Tucker and his staff have done this.

"We just have to work through these moments," Trestman said. "This is part of the NFL marathon. These are the day-to-day issues that you have: a new player, a young player, somebody you brought in off the street to try to help your football team, whatever it is. There's two ways to look at it and we just prefer to embrace the opportunity to bring these guys along to help them live their dream and hopefully be a part of our football team that can help us succeed down the road. And it's nothing that 31 other teams aren't going through right now in some way."

Coaches have help from veterans. Bostic this week has picking the brains of Pro Bowl linebacker Lance Briggs.

"Lance has taught me so much," Bostic said. "He's taught me a lot. Some things he teaches me he doesn't even know he teaches me. I watch a lot of those guys. I watch them more than they think I do. I ask them a lot of questions, but at the same time watching them as well."

Trestman looks at the slipping defensive ranking, but sees one constant: The Bears rank second in the league with 17 takeaways.

"Those turnovers win games," Trestman said. "Those turnovers aren't just the result of a guy catching the ball on the back end. They're a result of pressure, of guys being in the right place at the right time and we've had a lot of that during the course of the season."

NOTES: Tillman and tight end Martellus Bennett missed practice with knee soreness, and defensive end Julius Peppers was a coach's decision for a day off. ... Paea (toe), safety Anthony Walters (hamstring) and safety Major Wright (knee) participated on a limited basis. ... Wide receiver Brandon Marshall was fined $10,500 for wearing green cleats in the team's Oct. 10 win over the New York Giants.