Defense by the numbers? Fox says Bears will run 3-4

INDIANAPOLIS - As presumed, the Bears will run a 3-4 base defense, a scheme they've never used before.

How the current talent fits that scheme is still being evaluated.

"We've looked at a whole lot of tape," new Bears coach John Fox said. "Not as much as we need to; (but we'll) continue to do so. That'll help us define what we're going to be and how we're going to use the pieces.

"I'm confident we'll piece together a good defense. (But) we've not had a practice and, in my experience, players define that when you get to that point."

New defensive coordinator Vic Fangio had a top-five defense in each of his previous four seasons with the 49ers using a 3-4 scheme.

That's more than enough of a reason to switch from the 4-3, considering that the 2013 Bears gave up the most points (478) in franchise history and last year's group allowed the second most (442).

But the Bears won't be exclusively a 3-4 team. Just like almost every other NFL team, they'll still play some 4-3.

"You're in your base 3-4 a certain percentage of the time," Bears general manager Ryan Pace said. "But a lot of times you're in multiple defensive packages on third down.

"The best coaches find ways to maximize their players' skill sets. I know Vic's going to do that."

Even though the current defensive roster was built to play in a 4-3 scheme, it performed miserably. It's fair to wonder how well those same players will do in a new system.

If enough current Bears can make the switch and some new players can be acquired in free agency and the draft, the versatility of the 3-4 could help the defense improve because it gives the offense more to think about.

"The primary advantage of the 3-4 is you're not locked into which outside guys are rushing," Fox said. "That's a tremendous advantage in today's game.

"Even to the point where you've got guys that are a little bit comfortable in dropping (into coverage), you can drop eight. With today's spread offenses and some of the things people are doing with empty sets (only the quarterback in the backfield), that's an advantage."

Until players get on the practice field and perform in games, it's impossible to tell how well they'll transition.

Jared Allen has never been anything but a pass-rushing defensive right end, but he lacks the bulk of most 3-4 ends and, at 6-feet-6, 270 pounds, he may not have the athleticism to be an effective 3-4 linebacker.

But 4-3 defensive end Willie Young, at 251 pounds and with excellent movement skills, could be an ideal 3-4 linebacker - although he's coming off a torn Achilles.

"We'll line them both up there (at linebacker)," Fox said. "What they become is up to them.

"I haven't seen (Allen play linebacker), so it'd be hard for me to evaluate until we get him out there," Fox said.

"But he's a good football player, he's got good instincts, so my experience has been that works in a two-point or a three-point stance."

Last year's opening-day defensive left end, 6-foot-3 Lamarr Houston, was listed at 300 pounds, but he played at around 270. He's another question mark, not only as to where he fits in the new scheme, but how healthy he will be after suffering a torn ACL at midseason.

Pace is optimistic.

"I think (Allen) can be very flexible," the GM said. "We can use him in a variety of ways. Houston is the same way. I think position flexibility is a strength of some of those guys."

Whether 2012 first-round pick Shea McClellin has played defensive end or outside linebacker, he had only limited success in a 4-3 scheme. He remains a question mark to the new staff.

"I almost can't even say right now if he's going to be an inside or an outside 'backer until we get on the grass and watch him perform," Fox said.

They hope to have it figured out sooner than the last regime.

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