When Manti Te'o left South Bend to pursue a career in the NFL, his departure left a huge hole in the middle of Notre Dame defense.
His leadership, passion for the game and excellence on the field will be hard to replace, but the Irish aren't without defensive studs to step up to fill the void.
Last year's team went undefeated until the BCS title game because of its stifling defense. The offense only scored 25.8 points per game, which ranked No. 81 in the nation, while the defense allowed a paltry 12.8 points per game and finished with the No. 2 ranking.
Notre Dame's offense won't be much more explosive this year, either. Without any premier playmakers in the passing game, Brian Kelly's approach will continue to be conservative on that side of the ball.
This puts pressure on the defense to continue playing outstanding football, but thankfully there are a few key players on this year's roster capable of making life difficult on opposing offenses.
Louis Nix III, Nose Tackle
Every dominant 3-4 defense is anchored by a run-stuffing nose tackle, and Nix certainly fits this bill. At 6'3" and 347 pounds, he's a veritable monster in the middle.
But Nix isn't just a big body inside: he's an agile, quick defender who is capable of getting pressure on opposing quarterbacks up the middle and can also chase running backs down the line with excellent pursuit.
Last year, Nix made 7.5 tackles behind the line of scrimmage and tallied two sacks—impressive numbers for any defensive tackle, but much more so for a nose tackle.
Provided Nix stays healthy this year, Notre Dame's run defense will be among the best in the nation, and his presence in the middle of the field will cause opposing offenses no small amount of trouble.
Stephon Tuitt, Defensive End
If Nix is the anchor to Notre Dame's defense, then Tuitt is its wrecking ball.
As a sophomore in 2012, this 6'6", 303-pound defensive end was one of the most disruptive defenders in the nation. He racked up 13 tackles behind the line of scrimmage and tallied 12 sacks—unbelievable numbers for a 3-4 defensive end.
Should he decide to declare himself eligible for the 2014 NFL draft, Tuitt will likely be drafted earlier than Nix, who will probably be a first-round pick.
His immense size belies the fact that Tuitt moves as well as most tight ends and safeties. Quick feet, raw speed, incredible power and uncanny instincts make Tuitt one of the best defenders at any position in the nation.
Prince Shembo, Outside Linebacker
As was mentioned earlier, dominant 3-4 defenses are anchored by phenomenal nose tackles, but they also require excellent pass-rushers on the edge.
Shembo is ready to step up his game to another level in 2013 after displaying the ability to get after the passer in his first three seasons. As a junior last year he was the team's second-leading sack artist behind Tuitt, with 7.5 quarterback takedowns.
With Te'o gone to the NFL and Jarrett Grace coming in to replace him, the onus lies on Shembo to become more of a leader both in the huddle and on the field.
Double-digit sacks aren't out of the question for Shembo this season, and his ability to bring pressure off the edge will make life easier for the team's young secondary.
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