In August, few outside Notre Dame's locker room expected the Irish to play for a National Championship. Part of that pessimism revolved around the Irish starting an inexperienced quarterback, but another -- and probably larger -- reason involved the team's secondary.
Lo Wood's ruptured Achilles' tendon, suffered late in fall camp, thrust KeiVarae Russell into a starting role. Wood was expected to be a top contributor to a shaky group, but instead, a true freshman who never even played cornerback until August was thrust opposite of Bennett Jackson on the team's depth chart.
While Wood's injury looked to be a critical blow to Notre Dame's pass defense, those who had seen Russell in preseason practice had far more confidence.
"He was very athletic and he had a really quick first step, really quick first movements," Jackson said of his first impressions of Russell. "I thought he was someone who once he got tuned in a little bit would be a great benefit to the defense."
Cornerbacks coach Kerry Cooks saw the same thing.
"Some guys are just natural with feet and flipping their hips, and (have) gifted athletic ability," Cooks explained. "So he was one of those guys that I identified from day one, just having the ability to play corner and be able to do the jobs, to move lateral, to cover one-on-ones. You knew that once you saw him running around, that if he was willing to, he could be special."
By all accounts, Russell has put in the time and effort necessary for a greenhorn at his position. Cooks said Russell will incessantly ask him for feedback, as well as getting tips from Jackson and the rest of Notre Dame's cornerbacks.
"You got a kid like that's whos willing and open to expose himself to criticism and coaching, what more could you ask for?" Cooks said.
There's still plenty of room for Russell to improve, which can be said about the rest of the Irish secondary. But Notre Dame will enter the BCS Championship with the nation's No. 21 pass defense, allowing 194.4 yards per game and only seven touchdowns -- the same number of passing scores allowed by Alabama, and only bested by Boise State, Vanderbilt and Florida.
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As improbable of an achievement as that would've seemed before the season, after safety Jamoris Slaughter tore his Achilles' tendon against Michigan State, that kind of success seemed even less likely.
Slaughter's injury thrust Matthias Farley -- who redshirted as a wide receiver in 2011 -- into Notre Dame's starting lineup. While Farley played a little safety in high school, he admitted that experience didn't exactly carry over to college, especially when he trained as a receiver for his first year on campus.
He flipped to safety in time for spring practice in 2012, but had a ways to go before he could be considered as a viable backup.
"I thought hed probably help us on special teams and would be a guy that would learn through the year," safeties coach Bob Elliot said. "I thought he probably would need this year to figure out how to play defense."
Farley's high football I.Q. and dedication between spring and fall camp transformed him from an afterthought into a legitimate option. He's leaned heavily on Elliot, referring to the seasoned coach as being "monumental" to his growth. Having Motta -- the lone veteran among Notre Dame's secondary -- in his corner has been an asset, too.
"Just to see the way hes evolved, his reads and his understanding of the game has been pretty impressive," Motta said.
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Notre Dame's pass defense success isn't just the product of quality play from its four starters. Danny Spond has carved out success as Notre Dame's "dog" linebacker in its 3-4 formation, and Manti Te'o nearly leads the nation with seven interceptions.
Some will point to the ability of Notre Dame's front seven to put pressure on a quarterback as another reason for the success of the team's secondary, too. That's a fair assessment, although it's one Jackson bristled at earlier in the year. This is a prideful group, one that has used its doubters as motivation.
For this unit, a lack of experience hasn't mattered. Learning on the job has been par for the course, and so far, it hasn't come back to burn Notre Dame.
"They just took those baby steps, and finally youre starting to see them piece it all together," Cooks said. "And its been fun to watch that group go from zero to 10 by the end of the season. And now, their confidence is high, as well as it should be."