Roster breakdown: Defensive line

With teams game-planning to stop Julius Peppers, expectations are high for Tommie Harris, who said he's the healthiest he's been in years. Jerry Lai/US Presswire

Editor’s note: As the Bears prepare for their season-opener against the Lions at Soldier Field on Sunday, ESPNChicago.com breaks down the roster by position. Here's a look at the defensive line in this fifth installment.

Julius Peppers rag-dolled offensive tackles, exploded past them off the edge, and hurried worried quarterbacks regularly in limited preseason action.

That’s what the Bears paid for in handing Peppers $42 million guaranteed. The key now, though, is to coax the rest of a defensive line -- which is expected to see more one-on-one matchups with the arrival of Peppers -- to perform similarly.

The concept seems simple: Offenses will devote schemes and manpower to neutralize Peppers, thus freeing up other defensive linemen such as defensive tackle Tommie Harris, nose tackle Anthony Adams, and ends Mark Anderson and Israel Idonije to take advantage of one-one-one matchups. The reality, however, is what looks appealing on paper doesn’t always translate on the field.

That still doesn’t temper the club’s expectations.

“All of our guys who’ve played at an elite level, we’re expecting them to play better ball this year,” Bears coach Lovie Smith said in discussing Harris’ prospects for the upcoming season.

Outside of Peppers, who has averaged 10 sacks, in addition to forcing four fumbles per season over eight years, Harris -- who claims to be in his healthiest state in recent years -- could be one of the unit’s most determining factors for success. The expectation is for Harris to return to Pro Bowl form by utilizing his immense quickness to pressure passers up the middle while blockers are preoccupied with Peppers.

“We expect him to play the type of football that a player like Tommie is capable,” Smith said. “He’s a good player, been an all-Pro player, and we expect him to play at that form.”

The Bears should demand such production from both Harris and Peppers, considering they’ve invested in them a combined $60 million in guaranteed money. The duo could use help from Adams, Anderson, and Idonije, along with key reserves such as Marcus Harrison, Matt Toeaina, and Henry Melton, who figure to play vital roles in the defensive line rotation.

Since Smith took over as coach in 2004, just two Bears achieved double-digit sack seasons. Anderson, who plays defensive end opposite Peppers, made 12 sacks as a rookie in 2006, but has since tallied a combined nine sacks over the last past three seasons. Idonije partners with Anderson opposite Peppers. Despite playing six seasons for the Bears, Idonije has managed to net just eight career sacks, which clearly isn’t enough.

While bundles of sacks in 2010 aren’t necessarily paramount, consistent pressure from the front four is important because it allows flexibility on the back end. The Bears can’t afford to be forced into blitzing at a high rate to manufacture pressure, because it puts the secondary in vulnerable man-coverage situations.

“Are we going to be able to generate enough with our front four’s pass rush or aren’t we?” asked general manager Jerry Angelo in discussing the staff’s challenges in putting together a solid defense. “Or are we going to have to do more zone-blitzing? We need to figure out who we are. The guys we’re paying money to, the guys you’re building off of, they’ve got to play to their ceilings.”

Best-case scenario

Motivated to prove he’s worth the financial commitment, Peppers performs better than expected, and Harris returns to Pro Bowl form, while Adams continues his quiet steadiness as a run defender. If Anderson and Idonije manage to beat some of the one on ones brought about by extra attention paid to Peppers, the Bears can expect to generate plenty of heat, which in turn could lead to errant throws and interceptions. Rotational players such as Harrison and Toeaina also play huge roles in making the defensive line go, because they’ll be counted upon to win matchups with offensive linemen who’ve been worn down by Peppers, Harris, Adams and the combination of Anderson and Idonije.

Worst-case scenario

A serious injury to Peppers would be the worst, but a more likely scenario is Harris continues his mediocre play, and the rest of the defensive line fails to consistently win their respective matchups. It’s almost a given that teams will more or less shut down Peppers in some games because they’ll devote so much to taking neutralizing him. If the rest of the unit can’t beat one on ones brought on by all the attention given to Peppers, it’s almost as if the club wasted the money it spent on the defensive end. Another worst-case, yet realistic scenario based on the team’s preseason performances, would be a continued inability to consistently stop the run. If the defensive line can’t stuff the run, it can’t force teams to be one dimensional. That would make the Bears drop a safety into the box as a run defender, which in turn, would diminish the secondary’s ability to defend.