It’s really hard to put your finger on how good Tennessee’s run defense was last year. There are some stats that make you shake your head, and there are others that make you say ”wow.”

And there’s the eye test, of course. There are many ways to look at that, as well. The Vols are on a six-game winning streak, the third-longest active streak in the nation, and they might have been the most dominant team in bowl season. But they also lost four games last season, and it all four the defense gave up a late drive – or drives – that led directly to the loss.

Good or bad? It all depends on the moment.

Jan 1, 2016; Tampa, FL, USA; Northwestern Wildcats running back Warren Long (13) runs with the ball as Tennessee Volunteers defensive lineman Kahlil McKenzie (1) and Tennessee Volunteers linebacker Kenny Bynum (51) defend and during the first half in the 2016 Outback Bowl at Raymond James Stadium. Mandatory Credit: Kim Klement-USA TODAY Sports

Credit: Kim Klement-USA TODAY Sports

There were some stunning statistics as well, though. The Vols allowed third-down conversions only 27.6 percent of the time, the best rate in the SEC and second in the country to only Boston College. (Vanderbilt, Alabama and Georgia were Nos. 6-8 in the country.)

But they also allowed eight backs to rush for 100 yards or more, including two in one game (Alex Collins and Rawleigh Williams of Arkansas). That’s a stunning number for what is supposed to be an elite defense. Clearly, they weren’t.

Here’s a look at the Tennessee run defense:

2015 STATS

Rushing yards allowed per game (SEC rank): 151.6 (9th)
Most rushing yards allowed in 2015: 275 (Arkansas, Oct. 3)
Rushing TDs allowed: 13 (6th)
100-yard rushers allowed: 8, Detrez Newsome, Western Carolina (128 yards); Kelvin Taylor, Florida (102 yards); Alex Collins, Arkansas (154 yards); Rawleigh Williams, Arkansas, (100 yards); Sony Michel, Georgia (145 yards); Derrick Henry, Alabama (143 yards); Mikel Horton, Kentucky (109 yards); Ralph Webb, Vanderbilt (149 yards).

FRONT SEVEN

The Vols should be really stout up front, though depth may be an issue along the line. Kahlil McKenzie (pictured above, right) and Shy Tuttle are the likely starters at defensive tackle and Derek Barnett and Corey Vereen should be locked in at defensive end. That’s a lot of talent, but it hasn’t always been consistent.

McKenzie has the potential to be a star, provided he takes a nice next step up. Tuttle could be a star, too, and his season-ending ankle injury from a year ago shouldn’t be an issue. Barnett (below) is a legitimate star and Vereen, if he stays consistent more often, could be quite a force on the edges.

Jan 1, 2016; Tampa, FL, USA; Northwestern Wildcats running back Justin Jackson (21) runs the ball against Tennessee Volunteers defensive back Derek Barnett (9) in the second half at the 2016 Outback Bowl at Raymond James Stadium. Tennessee defeated Northwestern 45-6. Mandatory Credit: Mark Zerof-USA TODAY Sports

Credit: Mark Zerof-USA TODAY Sports

Linebacker is the strength of this defense. Jalen Reeves-Maybin could have jumped to the NFL but decided to come back for a senior season. Darrin Kirkland Jr. had some nice moments a year ago and seems primed for a big 2016. They might be the best 1-2 punch at linebacker in the league.

UT rarely used three linebackers last year, going with nickel packages quite a bit, and it will be interesting to see how much that changes under new defensive coordinator Bob Shoop.

WHO IS THE SECONDARY ENFORCER?

Cornerback Cameron Sutton (below) and safety Evan Berry both love flying to the ball. They have plenty of speed and like mixing it up when they have to. The Vols still have questions to answer in the secondary, but they can definitely contribute on the run.

Oct 10, 2015; Knoxville, TN, USA; Georgia Bulldogs wide receiver Malcolm Mitchell (26) catches a pass for a touchdown against Tennessee Volunteers defensive back Cameron Sutton (7) during the first half at Neyland Stadium. Mandatory Credit: Randy Sartin-USA TODAY Sports

Credit: Randy Sartin-USA TODAY Sports

GREATEST CONCERN

It’s just too obvious to point out that there’s no way the Volunteers can allow eight backs to rush for 100 yards or more again this year. For as much talent as they have on the defensive side of the ball, getting gashed like they did just isn’t acceptable. The 2016 season is one loaded with hype for Tennessee and if they want to win titles – division, conference, national – they are going to have to be tougher against the run.

ONE STAT THAT MUST IMPROVE IN 2016

Last week, we threw the Tennessee offense under the bus – and rightly so – for their ineptitude late in the Vols’ four losses last year. The dismal stats were staggering. Still, it was the defense that gave up the final points in all four games that led to the losses to Oklahoma, Florida, Arkansas and Alabama.

Oct 24, 2015; Tuscaloosa, AL, USA; Alabama Crimson Tide running back Derrick Henry (2) carries for a touchdown against Tennessee Volunteers defensive back Malik Foreman (13) during the first quarter at Bryant-Denny Stadium. Mandatory Credit: John David Mercer-USA TODAY Sports

Credit: John David Mercer-USA TODAY Sports

Here’s an ugly stat: After having fourth-quarter leads in all four losses, the Tennessee defense gave up six scoring drives to lose. The average drive was 11 plays and 73 yards. For as good as they were at getting off the field all year on third down, they didn’t do it down the stretch. That has to change. Here were the six scoring drives:

Oklahoma scoring drives:  14 plays, 80 yards. 13 plays 60 yards.

Florida: 17 plays, 86 yards; 4 plays, 59 yards

Arkansas: 10 plays, 80 yards

Alabama: 8 plays, 71 yards.

BETTER/WORSE IN 2016

The Volunteers’ mishmash of stats makes this a tough comparison, but let’s focus on the most important, and that’s winning the big games that matter for a team chasing titles. The Vols will be better stopping the run in 2016 because they will be better down the stretch. You won’t see fourth-quarter collapses this year with more experience on the field, and the only concern with that is if a rash of injuries hit the starters. The starting 11 looks awesome, but depth is still an issue.