Tennessee needed to find just enough defense in 2021
Josh Heupel turned Tennessee into one of the nation's best offensive teams in his first year, but what happened on defense? Expectations were much lower for that side of the ball entering 2021. The Vol defense had been terrible in 2020, was losing a lot, and Heupel's defenses at UCF left a lot to be desired.
There were also doubts about his DC hire Tim Banks. Banks had struggled as DC at Illinois from 2012-2015 and didn't serve as the play-caller at Penn State in the following five years. How well would be actually do?
The Tennessee front seven had to be rebuilt. They lost their three best disruptors from that group. Along the DL, they returned one primary starter and three other players with starting experience. Only reserves returned at LB.
There was a quite a bit more experience coming back in the secondary, with essentially the entire starting group returning. But there's a catch here: that group was awful in 2020. They ranked 105th in passer rating allowed at 151.8. So despite the experience, it was hard to feel good about having those players returning.
In the portal, they brought in LB Juwan Mitchell, CB Brandon Turnage, and DL Byron Young, Caleb Tremblay, and Da'Jon Terry. But again, plenty of players who'd largely been backups in 2020 turned into the starters.
We won't dive into any individual stats for the 2021 season because unlike the offense, there's no schematic comparisons to be made to what Mississippi State will be under Jeff Lebby. But for their overall defensive output, there wasn't a massive improvement.
The Vols allowed 29.1 PPG, just one point better than 2020, and their yardage allowed actually increased. Even when you adjust for their own offense's pace, which leads to more snaps ran on defense, they still didn't field a strong defense by any means.
What did improve for Tennessee was the frequency of negative plays they forced. They were far more effective at getting after QBs and forced more turnovers. Those few havoc plays made a big difference. Still, their improvement was mostly driven by their offense.