Bears switch to 3-4 defense in spotlight at OTAs

The overhaul of the Bears' defense continues with Wednesday's first of 10 OTA (organized team activity) practices at Halas Hall over the next three weeks.

That includes the conversion from a 4-3 alignment to a 3-4, which has become more popular in the NFL in recent years and is the preference of new defensive coordinator Vic Fangio.

Coach John Fox, who was a defensive assistant for 23 years before he became the Carolina Panthers head coach in 2002, has experience in both schemes. He chose Fangio as the foreman in charge of rebuilding a Bears defense that has fallen on hard times the past two years. Changing schemes won't make the rehab job any easier, at least in the beginning — but Fox believes there are advantages.

“The 3-4 has always been a little trickier (to attack),” Fox said. “It's different, so teams have to get ready for it in a short period of time. There are some disguises of it, (like) who the fourth rusher is.”

Although the additional pass rusher in most 3-4 defenses is usually an outside linebacker, the two inside linebackers could also factor into the pass rush.

“So I think it's a little bit of the element of surprise,” Fox said. “They do a good job of disguising, and I think (Fangio) is an excellent teacher.”

Off-season additions were made to the defense with the scheme conversion in mind. But Fangio says some of the Bears holdovers, who were acquired to fit the old 4-3 scheme, will find some of their abilities translate well to his version of the 3-4.

“The 3-4s that are being played in the league are all a little different,” Fangio said. “Some are drastically different, some a little different. I'd say we're kind of a combination of the old-school 3-4, but we play a lot of 4-3 principles, too, within a 3-4.

“We're not always going to be in a guy (head-up) over the tackle and a guy head-up on the center. We'll be in an under- or an over-looking front also, so it's kind of a hybrid.”

In the traditional “Okie 3-4,” the nose tackle is directly over the center with the defensive ends directly over the offensive tackles. All three players are responsible for the gaps on either side of their opponent.

In a “3-4 under,” a more aggressive alignment, defensive linemen play one-gap responsibilities similar to those in a base 4-3. They are usually shaded to either side of the offensive linemen across from them and their emphasis is on penetration rather than the read-and-react duties in the Okie 3-4.

Defensive end Ray McDonald's Monday arrest and subsequent release leaves the Bears somewhat shorthanded up front, so the play of 2014 draft picks Ego Ferguson and Will Sutton, rookie nose tackle Eddie Goldman and unrestricted free agent defensive end Jarvis Jenkins is even more crucial and will be more scrutinized.

“In any defense, and the 3-4 is no different, the three down linemen to me are the heart and soul of the defense,” Fangio said. If they're getting pushed around, it doesn't matter what you're in, we're in trouble.”

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