KNOXVILLE, Tenn. (AP) -- Tennessee linebacker Herman Lathers sees a bigger difference now in first-year defensive coordinator Sal Sunseri's 3-4 scheme than he did in the spring.
Lathers said that in the spring, players had trouble just lining up correctly, but a summer's worth of film study and visiting with position coaches has Sunseri pleased with the defense's progress.
"The start of the spring was rough, new coaches, new scheme," Lathers said. "A lot of guys didn't trust the stuff, but once spring got midway, a lot of guys seen the scheme works only if you follow the scheme and do what you're supposed to do.
"Playing in the defense is all about trust and being comfortable with who you're playing with. Trusting the guy next to you to do his job and make plays."
Sunseri still wants players developing toughness and working on fundamentals while adjusting to the new defense.
"Anytime you come in and you're a new coordinator -- regardless of what package you're running and what package you're applying -- everybody has to learn the language," Sunseri said. "I'm happy where it's at right now."
The Vols struggled to get pressure on opposing quarterbacks last season. Sunseri said the pass-rush "isn't where it needs to be," but it's improving and comes down to player discipline.
"It's about being able to read the offense," junior defensive lineman Daniel Hood said. "They don't know if we are going to blitz from an angle, in the middle or outside. That helps us to be more efficient in what we're doing. I don't think we are going to sit back on our heels and out-talent any team in the SEC. We are going to throw different schemes in there and be more aggressive."
Lathers, a fifth-year senior who has battled injuries and health issues throughout his career and missed last season with a fractured ankle, is adapting to playing middle linebacker in the defense. Sunseri called him the "quarterback of the defense" with his leadership and experience.
"We're not only expecting Herman Lathers to be a leader, we're expecting all the seniors to be a leader," Sunseri said. "I'm looking for 11 leaders out there going and getting the football."
Sunseri said sophomore linebackers A.J. Johnson and Curt Maggitt "might be the finest young linebackers I've ever coached."
Defensive end Darrington Sentimore played in a similar 3-4 scheme as a freshman at Alabama before transferring to Mississippi Gulf Coast Community College last season. Sentimore admitted he arrived in January overweight, and coaches noticed.
"I knew what it was. It was me not in shape," Sentimore said. "So, this summer I went out there and busted my tail on the football field to get in shape. Now, Coach Sal is pleased with me."
Daniel McCullers, a 6-foot-6, 377-pound defensive tackle and junior college transfer from Georgia Military Academy, is hard to miss on the field. He's working with the practice squad early in camp, but coaches believe he'll have a chance to contribute this fall.
"He's got a lot of work to do in understanding technique, understanding that he has more to cover than (a small) area and effort and all that stuff but he's a big guy and he's had a great attitude," Dooley said. "Now it is just a matter of how much he can learn and how quickly he can apply it."
Senior tight end Mychal Rivera is out with a sprained knee. Dooley said Rivera would be out "about a week or so." Freshman running back Davante Bourque is also out with a neck injury. Dooley said he didn't believe it was serious, saying it was a whiplash-type injury.
Senior walk-on Joseph Ayres, who started one game at defensive tackle in 2010, moved to tight end to provide depth. Dooley said the 6-foot-3, 273-pound Ayres has the ability to help this year as a blocker.
Freshman Justin King started fall camp working at outside linebacker, but was moved to the tight endhalfback role in the Vols' offense.
Wednesday was Tennessee's first full two-a-day practices of fall camp. The Vols took to the field in the morning and had another practice session in the evening.
After Thursday's practice, Tennessee will travel to Milligan College in Elizabethton, Tenn., where it'll practice from August 10-15.