Injuries force Bears' Fangio to deal with many moving pieces

It's not by design, but the Chicago Bears are providing a lot of young defensive players with valuable on-the-job training.

Injuries have already forced coordinator Vic Fangio to use 16 different starters on defense, eight of whom are rookies or second-year players.

And, as anyone who's perused the Bears' injury report knows, they're still dealing with a multitude of maladies. So Fangio will continue moving around his human chess pieces as he tries to make all the right moves.

Last week's lineup juggling worked well, as the Bears allowed a season-low 263 yards and just a pair of field goals in the 17-14 victory over the Lions. But eight defenders are on this week's injury report, so more tweaks could be in the works for Sunday's noon game against the Colts in Indianapolis.

"You just have to do what you have to do," Fangio said. "You're not given a lot of choices. We're playing a lot of guys, and even the guys that aren't so-called starters are getting a lot of play."

That's not necessarily a bad thing, as unexpected opportunities have helped youngsters get the playing time they need to develop. Because inside linebacker Danny Trevathan's thumb surgery, fourth-round rookie Nick Kwiatkoski and second-year man John Timu have each gotten one start, plus increased snaps when they didn't start.

Kwiatkoski made noticeable improvement from his Week 3 start versus the Cowboys to last week, when he got 44 snaps, even though Timu (19 snaps) started.

"Sometimes those guys are pretty wide-eyed when they go out there for their first NFL experience," Fox said, "and it was no different with Nick. Not that he was awful by any stretch. But it started a little slow for him. He started much faster (in) this last opportunity."

Trevathan returned to practice on a limited basis this week, fitted with a cast to protect his thumb, and the hope is he can function on Sunday, even without full use of his injured hand.

If Trevathan can't go, Kwiatkoski and Timu are better prepared to fill in than they were just three weeks ago.

"I feel like we're developing guys, even though they may not be starters," Fangio said. "We've had to do it at all three levels (line, linebacker and secondary). So, until we get a set roster, as far as from a health standpoint, we're just going to be playing the best combination we think we can for that game."

In the secondary, second-year man Bryce Callahan began the season as the No. 1 nickel cornerback, missed Week 3 with a concussion and then was promoted to starting corner last week. He responded exceptionally well, as 4 of his 5 tackles were solos that came within four yards of the line of scrimmage on pass plays that he nipped in the bud.

Cre'Von LeBlanc, an undrafted rookie from Florida Atlantic, was the nickel vs the Lions and played 76 percent of the snaps (48 plays). Glenn, who started the first three games at corner and mixed big plays and bad plays, still got in for 16 snaps. He grabbed an interception in the red zone that kept the Lions off the scoreboard.

The 5-foot-9, 191-pound Callahan took a huge step toward filling the void left by Kyle Fuller's knee injury.

"By cornerback standards in the league, (Callahan) would be considered a little bit short," Fox said. "But he's got a 41-inch vertical. He leaps pretty good. He's got quickness, he's got good awareness, and he's got good ball skills. That's something that we've kind of lacked a little bit of.

"When he's out there, we've got a guy that's got the opportunity to intercept the ball. I think his ball skills are what stand out to me."

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