Tennessee boasted a middle-of-the-pack defense in 2015, ranking eighth in the SEC in total defense and ninth in scoring defense during a 7-6 campaign.

But the Vols defense should be greatly improved in 2015, and that improvement could be the boost Tennessee needs to complete its quest to return back to the top of the SEC East standings.

The improvement begins with the return of star defensive end Derek Barnett, who was one of two SEC freshmen to break Jadeveon Clowney’s freshman sack record in 2014. Barnett registered 10 sacks, eight quarterback hurries and 20.5 tackles for loss during his rookie season, and what’s frightening is that he’s likely to add to those totals in 2015.

If you’re expecting a sophomore slump out of Barnett, don’t. He’ll be surrounded by other-worldly talents along the defensive line in the form of five-star 2015 signee Kahlil McKenzie and four-star defensive line signees Kyle Phillips and Shy Tuttle. Add in returning pass-rushing linebacker Curt Maggitt, who actually exceeded Barnett’s 2014 total with 11 sacks last fall, and you’ve got the makings of a deep, athletic front seven that should wreak havoc on the rest of the East.

This will allow Barnett to continue to dominate up front, as opposing offenses won’t be able to key solely on the star defensive end due to the amount of dynamic talent surrounding him. Granted, much of that talent will be making their own freshman debuts, but if their debuts are even half of what Barnett’s was in 2014 the Tennessee defensive line should be a force to be reckoned with come Week 1.

But even though Barnett is Tennessee’s leader on that side of the ball entering the coming season, there’s more to the defense than just a dominant front seven.

The Vols secondary returns plenty of playmakers as well, including starting safeties Brian Randolph and LaDarrell McNeil as well as cornerbacks Cam Sutton and Todd Kelly Jr (Sutton was among the conference leaders in passes defended with 13 in 13 games).

The loss of Justin Coleman on the outside may be difficult to overcome at first, but the Vols maintain plenty of experience throughout the secondary and the chemistry among the defensive backs should provide excellent balance to the aggressive front seven when opponents try to air it out.

And when opposing offenses try to run on the Vols stout defensive line, it won’t be much easier. Five of the team’s top six tacklers from a year ago are back for more in 2015, including linebacker Jalen Reeves-Maybin, a rising junior who led the team with 101 tackles last season.

Reeves-Maybin kept the defense afloat last season by stepping up into a greater role following the season-ending suspension of star senior A.J. Johnson, and he proved that he’s capable of being a productive linebacker for a full season when given the opportunity.

He’ll have that opportunity in 2015, and along with Randolph, McNeil, Barnett and Maggitt, the Vols have plenty of players who are not only capable but superb at tracking down ball-carriers and making tackles.

There’s been plenty of talk about the return of quarterback Joshua Dobbs for his first full season as UT’s starter under center. And with star tailbacks Jalen Hurd and Alvin Kamara behind him, a restocked offensive line in front of him and a bevy of athletic playmakers on the outside, the Tennessee offense should garner plenty of headlines this coming season.

But it’s actually Barnett and the defense that should make the ultimate difference in 2015, and if the sophomore and his pals can all translate their growth and development this offseason into results on the field this fall, UT is going to be mighty dangerous in an SEC East lacking an obvious threat as spring practice approaches.