Bears defensive picture remains muddled

INDIANAPOLIS - The phrase that best describes the 2014 Bears defense is: "We don't know."

With so much uncertainty, that's understandable. The Bears have enough players eligible to become unrestricted free agents on March 11 to field an entire defense. They can't afford to keep eight-time Pro Bowl defensive end Julius Peppers without a major contract restructuring, and they will try to get more out of Shea McClellin by moving him from defensive end to linebacker.

One thing the Bears do know about their defense is that it has to get a lot better than last year's stumbling crew, which was the worst in the NFL against the run and in the bottom quarter of the league in most pertinent categories.

"Obviously the most important part of this offseason is rebuilding our defense to a stature that's expected of us at Halas Hall, in our community and our fan base," coach Marc Trestman said Wednesday at the NFL Scouting Combine. He and general manager Phil Emery and their staffs will be fixated over the next few days on identifying draft-eligible players who can provide immediate help for the defense.

"It's going to be a defensive-oriented draft in terms of where we're going," Trestman said. "We know we're going to get younger (on defense)."

Adding multiple players through the draft and the inevitable loss of veteran free agents will facilitate the youth movement in a defense that is currently heavy on older players.

Cornerback Charles Tillman (32), linebacker D.J. Williams (31), defensive tackle Jeremiah Ratliff (32) and cornerback Kelvin Hayden (30) are among the Bears' unrestricted free agents with questionable futures in Chicago, in addition to Peppers, who is 33.

Defensive tackles Henry Melton (27) and Nate Collins (26) are both coming off season-ending ACL tears, making their value debatable and further muddling the Bears' defensive future.

Trestman and Emery are offering no clues as to how they prioritize the return of a large group of free agents.

"Certainly Charles knows we want him back, and we'll just work through it," Emery said of Tillman. "It's a step-by-step process."

On Melton, Emery said: "(There's) the same priority as it is to bring back any player that we would be interested in bringing back. And we do want to bring back Henry, and we'll work through that process."

As far as Melton's rehab, Emery said only: "He's making positive progress."

Trestman was more expansive on Melton.

"If you see him, you'll see that he has been training and he has been working," Trestman said. "He's very focused. You'll see he dropped some weight. He looks very good physically right now.

"He's committed to getting himself back, and he's got work to do to get there, but he's in a very good place right now, and we all understand the situation and we'll see where it goes."

As for the Peppers situation, Emery said: "He's part of our team. He's under contract."

Tillman is on record as wanting to return, and the Bears clearly want the Walter Payton Man of the Year Award winner back. But the two-time Pro Bowler is still playing well enough to command big bucks, even at his age.

"Charles is an extremely unique guy," Trestman said. "It just goes to his character and his personality and his leadership skills; and he's a terrific football player. He played very well, certainly when he was healthy. So he's extremely important."

Once the makeup of the defense has been determined - and the draft is still almost three months out - it will be a changed staff mentoring a younger crew.

Three new coaches have been hired to help with the defensive resurrection: Paul Pasqualoni (defensive line), Reggie Herring (linebackers) and Clint Hurtt (assistant defensive line). Martial arts expert Joe Kim has also been added as a consultant to help improve players' hand placement as they joust with opponents.

The Bears will retain their base 4-3 alignment but hope to have the flexibility to throw a change-up occasionally by utilizing 3-4 characteristics to keep offenses guessing.

"We're looking at the existing scheme and going through the process of putting a system of football together to accommodate the players that we have when we get going," Trestman said. "(But) we're not going to know who those players are for quite some time."

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Bears defensive unrestricted free agents

LB James Anderson

CB Zack Bowman

DT Landon Cohen

DT Nate Collins

LB Blake Costanzo

CB Kelvin Hayden

CB Sherrick McManis

DT Henry Melton

DT Jeremiah Ratliff

S Craig Steltz

CB Charles Tillman

LB D.J. Williams

DL Corey Wootton

S Major Wright