KNOXVILLE - Short on quality, experienced depth, Tennessee's defense is using spring practice to search for solution to build as much of is it as possible.

The Volunteers have attempted to teach their linebackers all three positions in each of the last two seasons, and now UT is experimenting a bit more by cross-training its defensive line.

"You always look as a coach to where your best 11 (players) are," defensive line coach Lance Thompson said earlier this week. "That's why it's good and healthy to have them cross-train at other positions so they're not just learning it day one when a kid gets hurt or you've got to put them in there. I don't think there's any damage in guys learning the whole front and the dynamics of the front."

Though reinforcements should arrive in June, the Vols currently are short on bodies along the defensive line. In effort to combat that lack of depth, some guys are learning both tackle and end. Tackle Marlon Walls was moved to end this week, and end Corey Miller has slid inside some.

"Moving Marlon outside isn't an indictment on Marlon or the other defensive ends," defensive coordinator Justin Wilcox said. "It's trying to create our best depth, and those two guys, Marlon and Corey, may have to be able to play both sides, inside and outside. That's just the way we're going about it, and we knew we were going to do that all along. We just need to develop our depth, and to be able to do that, we need to cross-train a couple of our guys."

Shifting guys inside or outside along the defensive line isn't a whole new concept. Wilcox did it at Boise State and also some last year, especially in passing downs when the Vols would occasionally play four ends across the line.

Teaching guys to learn multiple positions isn't new for Thompson, either. He's cross-trained the Vols' linebackers each of the past two seasons before moving to his new staff spot this year. Two seasons ago he moved backup outside linebacker Savion Frazier to the middle after Nick Reveiz's season-ending injury.

Though it always depends on the personnel, cross-training defensive linemen might be simpler than teaching a linebacker three different positions.

"You're playing a shade left or a shade right, and so you're going to see similar blocks along the front four," Wilcox said. "Now, certain body types are going to hold up better on double teams and those types of things.

"You don't want to be handcuffed if, well, he's only a three-technique and our two ends got hurt, but he can't play end because he only plays three-technique. To me that's not smart. You've got to be able to get your best guys on the field to help you play the game."

The Vols also don't have much more depth or experience at linebacker, leaving the task of increasing players' versatility without putting too much on them mentally up to Peter Sirmon, in his first year in charge of UT's linebackers.

"You can't get necessarily more players so you've got to get players that can play more positions," he said. "I think you've got to make sure you identify the players that mentally can take on that challenge and continue to push them. Some guys it's really easy to take on all three because they can step back and see how the pieces of puzzle work together, and some guys it's a challenge to figure how my one piece works in that puzzle. It's a challenge to master more positions with a little experience."

The adjustment won't be too large for the defensive linemen End and former Ooltewah High School star Jacques Smith admitted his surprise at not getting any looks inside in last Saturday's scrimmage.

"Coach Wilcox," Smith said, "he switches us around wherever the best feel for the defense is. We switch it up, so you never know what's going to happen."

Which is just what Wilcox prefers.

"You want to be careful how much you give them because then they start thinking instead of playing," he said. "It's a fine line, (but) we're going to ride that line. Lance will get those guys ready to go. He's done an awesome job with that crew, and I'm not worried about them learning it."

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