There’s an old saying that I always find myself coming back to.

If you can’t stop the run, you can’t win in college football.

That’s especially true in the SEC. There were six SEC teams that ranked 90th or worse in the FBS against the run last year. They were a combined 18-30 in conference play and none of them finished with a winning record vs. the SEC.

On the flip side, five SEC defenses ranked among the top 40 against the run. Those teams were a combined 28-12 in SEC play, all of them finished in the top three of their respective divisions, and none had a losing record.

So if you see a direct correlation between these SEC defense rankings and projected overall success, that’s probably why.

14. Missouri

You could look at it either way. Nobody returns fewer defensive starters than Missouri, but that was from a unit that finished 116th in yards allowed last year. Perhaps the Tigers need an identity change. Replacing NFL first-round pick Charles Harris won’t be easy. Barry Odom’s squad has to find some stars along the defensive front. Perhaps Terry Beckner Jr. can stay healthy and become the game-changer the Tigers so desperately need.

13. Ole Miss

The Rebels might be one of the more entertaining teams to watch in 2017, but not because they’ll be shutting down opposing offenses. Ole Miss could get into its fair share of shootouts, which became the norm last year, too. How different will this group look under former Auburn defensive backs coach Wesley McGriff? He’ll have to fix the SEC’s worst run defense. Marquis Haynes will need some help if the Rebels are going to win a game without needing to score 40 points.

12. Mississippi State

Mississippi State’s defense might not have been as bad as the numbers indicated — the Alabama and Arkansas games skewed those numbers — but this was still a unit that made things too difficult for the offense. Allowing 35 points to UMass and 41 to Samford is inexcusable for an SEC defense.

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New defensive coordinator Todd Grantham is tasked with turning around a defense that finished 110th in yards per game (500-plus in SEC play). Can he maximize the ability of promising young players such as Jeffery Simmons and Leo Lewis? That could determine how much — if any — improvement we see from the Bulldogs.

11. Kentucky

There’s good news and bad news with Kentucky’s defensive outlook. The good news is that the Wildcats return nine defensive starters. The bad news is, that’s from a unit that finished 86th in scoring defense last year. Giving up 40-plus points to the likes of Southern Mississippi and New Mexico State had something to do with that. With Jordan Jones and Denzil Ware, the Wildcats have two guys who could earn first-team All-SEC honors. But Kentucky won’t post its first winning record in conference play in 40 years unless it gets help up front and stops the run.

10. Arkansas

Arkansas had the season it had because it rarely won the battle in the trenches. That must change on the defensive side in 2017. With a new defensive coordinator, a new 3-4 scheme and some key pieces returning, this unit could make strides. But that can only happen if the Hogs get improved defensive line play. Guys like T.J. Smith will have to become big-time contributors in order for this unit to overcome last year’s issues.

9. Tennessee

What to make of Year 2 of Bob Shoop? Injuries obviously gutted that defense beyond repair in the second half of 2016. That won’t be an excuse for lackluster play in 2017, though. With Shoop’s new staff, many expect the Vols to look like a different unit, despite the fact that they lost UT all-time sacks leader Derek Barnett. They do return seven starters on defense, though the Darrin Kirkland injury couldn’t have come at a worse time. Whoever is on the field will have to improve Tennessee’s dreadful run defense.

8. South Carolina

The Gamecocks should be better all around in Will Muschamp’s second year. The defensive improvements should be noticeable. Skai Moore and Bryson Allen-Williams should lead a solid group of linebackers. The questions are up front. The Gamecocks were gashed for 200-plus rushing yards per contest last year. Can new interior defensive line starters pick up the slack? They better, because South Carolina faces four straight 1,000-yard backs after the season opener.

7. Texas A&M

Losing Myles Garrett was obviously a major bummer for the Aggies, as was losing a key member of the secondary in Justin Evans. Couple that with the fact that the Aggies’ defense struggled as much as it did last year (especially against the pass), and it’s easy to be down on their chances in 2017.

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But John Chavis still has an opportunity to make good on that rich contract. Keep in mind that Texas A&M still finished 40th in scoring defense, and it returns seven starters on that side. Getting Armani Watts back healthy will be huge, as will the return of Justin Dunning. The Aggies could be better than this ranking by season’s end.

6. Vanderbilt

Credit Derek Mason for what he’s been able to turn the Vanderbilt defense into. This year should be another reminder of that. With seven starters back, the Commodores have plenty of experience and talent to repeat last year’s effort. Oren Burks should be able to fill Zach Cunningham’s role, and the line should still be solid with Nifae Lealao leading the way. But the secondary must improve (83rd vs. the pass). Underclassmen such as Joejuan Williams, who Mason compared to Richard Sherman, will have to step up.

5. Auburn

Auburn relied on its defense too much last year, just like Florida and LSU did. It shouldn’t have to do that as much in 2017, but the Tigers should still stymie plenty of foes in the second year of Kevin Steele’s defense. As a unit that lost four players to the NFL, Auburn will have some major tests early on. Matchups against Clemson, Missouri, Ole Miss and Mississippi State in the first half of 2017 might make last year’s No. 7 FBS scoring defense ranking tough to repeat.

4. Florida

Losing seven (!) defensive players to the NFL hurts, but the Gators will still be carried by their defense in 2017. With Duke Dawson leading a young but talented secondary, this unit should still be one of the nation’s best against the pass. Cece Jefferson has loads of potential to lead what should be a solid defensive line. The question is the same as it’s been in each of the first two years of the Jim McElwain era. Can the defense get some help from the offense against quality foes? Allowing 33.3 points per game to top-25 foes like they did last year won’t push the Gators into the nation’s elite.

3. Georgia

On the surface, this is perhaps the boldest call of any on here. The Bulldogs finished tied for fifth in the SEC in scoring defense in the first year of the Kirby Smart era. In Year 2, there’s a lot to like.

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The Bulldogs have 10 starters back from a unit that improved significantly in the second half of 2016. After the devastating Tennessee loss, Georgia surrendered 19.75 points per game overall and just 17.2 points per game in SEC play. If Lorenzo Carter and Trent Thompson put it all together, the Bulldogs will be vastly improved.

2. LSU

Two words: Dave. Aranda. There’s a reason this guy makes the big bucks. It’s because he can walk into any situation and produce a top-flight defense. No Arden Key? No problem. Got an offense that can’t sustain drives? That’s alright. Watch your top defensive backs get drafted in the first round? No worries. Pencil LSU in for another top-10 defense in 2017.

1. Alabama

Bold, right? Saying the Tide will have the top defense in the SEC is like predicting Lee Corso will say at least one nonsensical thing during the first College GameDay. It’s inevitable. Even with all the players Alabama lost to the NFL from the front seven, this group is still locked and loaded for another year of dominance. Besides, the Tide might have the best secondary in America. The defensive touchdowns might not be sustainable, but don’t bet on Alabama having a down year on defense. Ever.