The key to the team's overall success is its defensive front, one that stops the run first, then attacks the passer with 31 of the defense's 34 sacks courtesy of its defensive linemen and their reserves. Notre Dame's pass defense has been a pleasant surprise as a result, ranking 12th in pass efficiency defense while allowing just seven touchdown tosses this fall, tied for fourth fewest nationally.
No team scored more than two touchdowns vs. the Irish in 2012 and defensive coordinator Bob Diaco's unit kept six teams from hitting pay dirt including a stunning four consecutive, three of which were ranked at the time: Michigan State, Michigan, Miami, and Pac-12 champion Stanford.
Below is a look at five key Notre Dame defenders, each of whom played a vital role throughout the 2012 season as the offense struggled for an identity through the first seven games.
LB #5 Manti Te'o -- Entering his senior season, Manti Te'o had recorded 28.5 tackles-for-loss as a havoc-causing, gap-plugging inside linebacker. Lacking on his statistical resume, however, was the presence of a single turnover secured: no interceptions, no fumble recoveries.
Fast forward 12 games and the Heisman Trophy finalist is the owner of seven interceptions -- most by a linebacker in college football this decade -- and three fumble recoveries. In addition to those 10 turnovers, Te'o created a trio of his own, pressuring three enemy passers into interceptions secured by Irish teammates.
Te'o was asked to shore up Notre Dame's porous middle-zone defense this fall and he responded with the best pass coverage effort by a Notre Dame 'backer in program history. The team's leading tackler for the third straight season -- each in excess of 100 stops -- Te'o also led the Irish in passes defended (11) while tying for fourth in tackles for loss (5.5).
Throughout 2010 and 2011, his sophomore and junior seasons under Brian Kelly, Te'o's instincts and attacking style nearly eradicated the screen pass from opposing game plans. This fall, it was his reaction time, film study, newfound quickness (he lost 10-plus pounds in the off-season), and tackling prowess that negated the middle of the field for opposing quarterbacks.
NG #9 Louis Nix -- Te'o is the team's best player, but the massive Nix ranks as No. 1A in terms of importance. The nation's most underrated nose guard, Nix will likely be the best player Alabama center Barrett Jones has faced this season, making the middle of scrimmage the game's focal point for coaches and casual fans alike.
Nix, who two years ago was unable to get into a proper football stance at 365 pounds, has dominated the middle of Notre Dame's shifting 3-4/4-3 scheme, finishing with 45 tackles (5.5 for loss) and five passes defended. But as with most interior defenders, numbers don't reflect his true value.
Rarely single-blocked, the 6'4" 330-pound Nix has allowed teammates Stephon Tuitt (12 sacks), Prince Shembo (10.5) sacks, and Kapron Lewis-Moore (8.5 tackles for loss) to often work one-on-one. Tuitt has garnered All-America honors as a result while both Lewis-Moore (a 5th-year senior) and Shembo (a junior hybrid LB/DE) are now major pro prospects.
As Nix goes, so too will the Irish efforts vs. Alabama's standout offensive front.
DE/DT #89 Kapron Lewis-Moore -- Spring 2012 was not kind to the 5th-year senior and previous three-season starter. Slated for rotational duty behind wunderkind Aaron Lynch and coming off a torn ACL in October 2011, Lewis-Moore was working his way back into shape as the future of the Irish defense, Lynch and fellow sophomore Stephon Tuitt, dominated headlines.
Lynch transferred to South Florida shortly thereafter, Lewis-Moore rehabbed and began to better carry 305 pounds, and months later, the 23-year-old man that entered South Bend a 220-pound edge rusher has morphed into a legitimate NFL prospect and nearly unblock able player up front.
A sub-par pass rusher prior to 2012, Lewis-Moore finished with nine QB hurries, six sacks, and a pair of forced fumbles to go with 8.5 tackles for loss. He's the unit's second-best player (behind Nix) over the last two months, registering a tackle-for-loss in seven of his last eight games and sack in five of the last seven outings including a key third-down take-down vs. USC.
Few 5th-year players have benefitted more from added time in South Bend than did Lewis-Moore this fall.
DE/DT #7 Stephon Tuitt -- A true sophomore, the 6'6" 300-pound Tuitt arrived ahead of schedule, securing a team-high 12 sacks (1.5 short of Justin Tuck's program record), three forced fumbles, nine QB hurries, a blocked kick, and most impressive if not important, a stunning 77-yard sprint for a touchdown in the season opener after a fumble recovery vs. Navy.
Through weekly Irisheyes.com film reviews, Tuitt ranked as one of the team's top 10 players (both sides of scrimmage considered) in nine games this season, earning honorable mention honors in the other three. The Monroe, Ga., native lines up as an edge rusher when the defensive front shows a 4-3 alignment, as a covered defensive end in the 3-4, and at times, on the nose in nickel packages though Lewis-Moore more often occupies that spot of late.
Tuitt earned 1st Team All-America honors from CBS Sports.
S #17 Zeke Motta -- If not for Te'o, would rank as the defense's most improved veteran player for 2012. A part-time starter in 2010 and 2011 at safety, Motta entered 2012 as an experienced, but inconsistent defender, one that had recorded few plays of impact over 38 games played and inexplicably missed open tackles in space at key moments. He now ranks as the secondary's most important player -- the group's only true defensive back and a veteran surrounded by first-year starters, each of whom entered Notre Dame as an offensive player, two of which made their defensive debuts this fall including true freshman Keivarae Russell, whose first-ever snap (at any level) at cornerback came in the season-opener.
An aggressive, old school safety who offers plenty of action through the whistle, Motta finished second to Te'o with 61 tackles despite often roaming the defensive backfield as the team's post safety. Alabama has faced faster players, more productive players, and far better ball hawks than the 6'2 215-pound Motta, but none of them likely finished tackles with as much aggression and power as does the leader of the Irish defensive backfield.