Will linemen be better in Chicago Bears' new defense?

All eyes will be on the big guys up front in the new defense when the Bears begin their 14th consecutive training camp at Olivet Nazarene University in Bourbonnais with Thursday's non-padded practice.

The bigs will be easy to spot because in the Bears' shift to a base 3-4 alignment the linemen will be bigger than ever.

But will they be better?

If the answer is “no,” it will be another disappointing season for a unit that has been one of the NFL's worst in each of the previous two seasons. Auditions for the D-line begin in earnest Saturday with the first practice in pads, and coach John Fox knows what he and defensive coordinator Vic Fangio will be seeking.

“It's really just strength at the point (of attack),” Fox said after the final minicamp in mid-June. “(And) some of the transition from run (stopping) to pass (rush). How well can a guy convert to a pass rush? How stout are they? A lot of the things we're teaching here in the underwear (at minicamp), we'll see if they translate into pads.”

Linemen are not the primary pass rushers in Fangio's version of the 3-4. That responsibility falls to the outside linebackers, where many of last year's defensive ends now reside. (The Bears will revert to a 4-3 alignment on passing downs).

Last year's rookie tackles, third-rounder Will Sutton and second-rounder Ego Ferguson, remain linemen in the 3-4, but it has yet to be decided whether they will line up in one of the outside/end positions or in the middle at nose tackle. Neither has the prototypical mass of a classic 3-4 nose tackle.

That's not a problem for this year's second-round pick, 6-foot-4, 336-pound Eddie Goldman. He seems tailor-made for the nose, although 6-4, 303-pound, 11-year veteran Jeremiah Ratliff made four straight Pro Bowls (2008-11) playing nose tackle in the Dallas Cowboys' version of the 3-4. They could wind up sharing the job.

The Bears' only splash signing in free agency was former Raven Pernell McPhee.

The 6-3, 280-pound linebacker is expected to be the centerpiece of the defense and immediately impact the pass rush and create mismatches wherever Fangio deploys him. McPhee lined up in most of the front seven positions in Baltimore, where he had a career-best 7½ sacks despite playing just 49 percent of the Ravens' snaps.

Asked about McPhee's strengths, Fox said: “Strength. He's a powerful man. When you put him over a tight end, or even put him over a tackle, he matches up well. His strengths are more going forward than going backward. I see a big, powerful guy that's got some flexibility in a system, whether it's in a 30 scheme, where he's a penetrating rusher inside, or even off the edge.”

Shea McClellin, the Bears' 2012 first-round pick, also will be under the microscope. He, too has demonstrated versatility — but not in the same positive way as McPhee.

Originally tried as a defensive end, where he was miscast, McClellin was shifted to outside linebacker last year but did not produce the desired results. He had just 1 sack, leaving him with a three-year total of 7½. He will line up at inside linebacker this year.

“I feel comfortable,” McClellin said of his new position. “I haven't played inside for a long time, but it's starting to come back to me. The instincts to play in there are coming back. It's just a start. It's not where we want to be, but we'll continue to build.”

On the back end, cornerback Kyle Fuller, last year's first-round pick, was singled out early on by Fox as a building block. It should be entertaining watching Fuller match up in practice against this year's first-round pick, big, explosive Kevin White, and veteran Alshon Jeffery.

Jeffery is the de facto No. 1 wide receiver now that Brandon Marshall is where he can do the Bears the most good, on the New York Jets' roster.

“He's a longer, bigger guy at the corner position,” Fox said of Fuller. “Offensively we've got some pretty good skill guys. I just see him getting better every day.”

And whenever monotony sets in, coaches always can match Fuller against tight end Martellus Bennett for a little excitement.

That would be worth watching. A year ago during a training-camp practice, the 265-pound Bennett body-slammed the 190-pound Fuller after the rookie tried to rip a ball from the tight end's hands, yanking him to the ground in the process. Bennett was fined and suspended for his behavior, but it was one of the highlights of camp.

Next: What to watch on offense.

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Here are the key dates for Bears training camp. Practices generally last two hours. All dates are subject to change, so visit chicagobears.com for the latest updates.Wednesday: Team reports, no practiceThursday: 9:35 a.m. practice (no pads)Friday: 1

Bring on the Bears