SOUTH BEND, Ind. -- Joe Schmidt has gone from paying his own way in college to becoming the leader of Notre Dame's defense in less than a year. The inside linebacker from USC country was the talk of this spring for the Fighting Irish's revamped unit, adapting to new coordinator Brian VanGorder's scheme and unofficially carrying the mantle for the rest of the group, at least based on comments from his coaches.

Considering this one from VanGorder on the difference in the knowledge base between Schmidt and the rest of the linebackers: "There's a significant difference. Very bright player."

Or this, from head coach Brian Kelly, on defensive leaders: "Joe Schmidt is the leader on our defense. There's no one probably that has the kind of leadership and understanding of our defense than Joe has right now. Right now he can't come off the field. His knowledge base in terms of getting people lined up and having them execute what we do defensively -- he's absolutely integral to what we're doing."

So how did a player who was a walk-on until last June become an irreplaceable piece so quickly? Football Intelligence -- or FBI, as Kelly calls it -- is a phrase thrown around regularly by those describing Schmidt, who credits his history of playing a bevy of positions in his advance understanding of the game's intricacies.

A Pop Warner and early prep path that saw the Orange, Calif., native go from lineman to quarterback to defensive back gave Schmidt a wealth of knowledge by the time he was just a sophomore at Santa Ana Mater Dei High.

"I think that at a young age I had a lot of good coaching, and then I think I learned to think about the game in the right ways so I think about it more -- instead of like memorizing things I think about how everything fits together," Schmidt said. "So if the safety's moving here, where I got to move in relation to that, that's just how I think, and I think it's really benefited me with going at different defenses from high school to college and here switching a little bit."

Opportunity presented itself last season, as Jarrett Grace and several other regulars went down with season-ending injuries. Schmidt ended up notching a game-clinching pass break-up to clinch a win over his hometown Trojans. He finished 2013 with 15 total tackles, playing in all 13 games but starting none.

With VanGorder arriving to Notre Dame, bringing a more aggressive approach with him, the 6-foot-½, 230-pound Schmidt served as a quick learner in March and April, looking more and more like a guy who has a starting job locked up going into 2014.

VanGorder, for his part, has said that Schmidt is the type of guy a coach easily gets attached to.

"He's just uniquely bright," VanGorder said. "I'm talking, to the professional league and all, he's a very bright player."