A "nasty" defense made its return appearance in Neyland Stadium on Tuesday night.

There were sacks. There were momentum-changing interceptions. There was the same kind of speed and intensity Tennessee coaches got used to seeing a year ago.

"We’re young in the middle, but the main thing Chief (defensive coordinator John Chavis) says is if you go full speed, we’re going to be in the right spot and make plays," linebacker Ryan Karl said. "Don’t worry about being wrong. Go full speed all the time and have that nastiness."

Karl, a 6-foot, 225-pound junior linebacker, definitely brought his nasty.

It was Tennessee’s final major scrimmage of fall camp with a best-against-the-rest format, especially in the first half.

The title of best definitely went to the defense.

Karl had six tackles, two tackles for a loss, an 8-yard sack and one pass breakup where he batted a Bo Hardegree pass in the air and Marvin Mitchell snagged it for a 24-yard interception return for a touchdown.

"We just came out there today and got after them," Karl said. "When you get after them like that, they’re going to have some mishaps and have some turnovers."

With the first team playing primarily against a second or third-team offense simulating California, the defense allowed only 35 yards of offense on seven drives.

That included a Jonathan Wade 27-yard interception return to the 3, setting up the only touchdown for the first-team offense, a 4-yard pass from Erik Ainge to Robert Meachem.

"That’s what good defenses do," Wade said. "You work hard and you hope you have an opportunity to make plays.

"It’s one big defensive effort. If it wasn’t for the linemen getting that rush, and the linebackers putting pressure on the quarterback, a lot of plays won’t be made."

All in all, UT’s defense made seven sacks and finished with four interceptions, all on Hardegree. Adam Myers-White and Antonio Wardlow added the other picks in the second half.

Freshman linebacker Dorian Davis led the reserve defense with seven tackles.

Depth Issues Continue: UT coaches are still looking for some much-needed depth to develop in the defensive line and offensive line.

"At times there’s a considerable dropoff between most of the ones and the guys who are second team," UT coach Phillip Fulmer said. "If we have to play with three defensive tackles, and three defensive ends, and four or five linebackers, and seven offensive linemen, that’s the way we’ll have to play.

"Those guys playing will have to show a whole bunch of mental and physical toughness. But we only have to put 11 on the field at a time."

Centered: UT continued to take a long look at junior Michael Frogg and redshirt freshman Josh McNeil as first-team center.

"Right now, those guys are so close, it’s a hard call to see who goes out there first," Fulmer said.

McNeil got the opening nod but made the biggest mistake. He snapped the ball over Ainge’s head as the quarterback was waiting in the shotgun formation.

"That kind of really ruined my day," Fulmer said. "A couple of things like that, those things will get you beat."

Junior wide receiver Robert Meachem, who was moving in motion, recovered the fumble.

It was McNeil’s first miscue with the center-quarterback exchange since he and redshirt freshman Jonathan Crompton struggled with the snap in UT’s first public scrimmage on Aug. 12.

"I thought, overall, we were very sluggish up front today," offensive line coach Greg Adkins said. "I didn’t think we got a lot accomplished up front."

Sophomore Ramon Foster played extensively at left guard with the first team. Adkins said that was simply to test Foster’s endurance. Senior David Ligon is still expected to be the starter.

Mapu Getting Close: Junior defensive tackle J.T. Mapu could see plenty of action when California visits UT on Sept. 2.

Fulmer said coaches hope Mapu can provide 20 to 30 snaps. He’s still trying to regain his football conditioning after returning to Knoxville from a two-year Mormon mission.

Injury Update: The Vols made it out of the scrimmage relatively injury free.

Backup running back Ja’Kouri Williams left with a sprained ankle.

Starting fullback Cory Anderson limped off the field after the scrimmage with a slight knee injury. It didn’t appear serious.

Dave Hooker contributed to this report.