Mike Vrabel didn’t play for Jim Tressel at Ohio State; it only feels like he did. The Akron native and former Buckeye defensive end finished his career in Columbus a few years before Tressel’s arrival, but it appears he’s mastered Tresselball all the same.

You could say the primary tenets of Tresselball were as follows:

Limit big plays on defense Attack on third downs Win the red zone Don’t do anything stupid on offense

Granted, that recipe isn’t copyrighted by the former OSU head coach, but he certainly mastered it. He won a lot of games in Columbus by running the ball, avoiding crippling mistakes, and playing sound, physical defense that got more sound and more physical the closer you got to the end zone.

Vrabel, meanwhile, has won three of his first four games as the Tennessee Titans’ head coach by doing exactly the same thing.

Tennessee is among the NFL’s best at preventing big plays. The Titans allow opponents to create only semi-manageable third downs, and then they shut you down. And if you are lucky enough to create a scoring opportunity, they play maybe the league’s best defense inside their own red zone. They have invested a lot in the cornerback position of late — they brought in Malcolm Butler and Logan Ryan as free agents and spent a high pick on Adoree’ Jackson in 2017 — and have thus far gotten their money’s worth.

This is a damn good defense, one of the best in the league.

The offense, on the other hand?

The Titans have thus far been unable to avoid unfavorable third downs and unable to convert them once they’re there. They create no big plays to speak of. They are 28th in scoring offense. Their biggest skill so far has been their ability to turn the ball over less than their opponents.

Granted, quarterback Marcus Mariota has been hurt. He injured his elbow in Week 1 against Miami, and then, despite lacking feeling in his fingers, he had to return to action ahead of schedule in Week 3 when backup Blaine Gabbert suffered a concussion.

The Titans have undoubtedly been better offensively with a healthy-ish Mariota in the lineup.

TEN offense, weeks 1 and 4 (Mariota semi-healthy) : 23 PPG, 5.6 yards per play, 38% success rate

: 23 PPG, 5.6 yards per play, 38% success rate TEN offense, weeks 2 and 3 (Mariota injured/limited): 14.5 PPG, 4.6 yards per play, 34% success rate

That’s the difference between an average offense and a horrid one. And if you’ve got a good defense, maybe average is all you need.

Still, the Titans’ 3-1 record has been powered by three consecutive three-point wins. To say the least, that’s pretty hard to maintain. Impossible, even. Among the NFL’s seven 3-1 teams, Tennessee’s path has been the least sustainable, and it’s not particularly close.

Here’s a quick glossary:

Second-order wins: Take all of a game’s key stats (the ones above, plus a few other stragglers), toss them into the air, and basically say “based on these key stats, you could have expected to win this game X percent of the time.” Add each game’s post-game win expectancy together (a 50 percent probability = 0.5 wins), and you get a team’s second-order win total.

Margins (yours minus your opponent’s):

Marginal efficiency : a team’s success rate, adjusted for down, distance, and field position.

: a team’s success rate, adjusted for down, distance, and field position. Marginal explosiveness : a team’s explosiveness (as measured by Isolated Points Per Play, or IsoPPP), adjusted for down, distance, and field position. You can learn more about marginal stats here.

: a team’s explosiveness (as measured by Isolated Points Per Play, or IsoPPP), adjusted for down, distance, and field position. You can learn more about marginal stats here. Scoring opportunities : drives in which you achieve a first down inside your opponent’s 40 (or score a touchdown from outside the 40). For pro football, I also include drives that result in a field goal attempt, whether or not there was a first down inside the 40.

: drives in which you achieve a first down inside your opponent’s 40 (or score a touchdown from outside the 40). For pro football, I also include drives that result in a field goal attempt, whether or not there was a first down inside the 40. Points per scoring opportunity, field position margin, and turnover margin : exactly as they sound

: exactly as they sound Turnovers luck: the difference between a team’s turnover margin and its expected turnover margin, which is determined using long-term fumble recovery rates (which regress toward 50 percent over time) and the long-term ratio of interceptions to pass breakups (typically about 1-to-3.5).

Second-order win totals suggest that Jacksonville, New Orleans, Baltimore, and Cincinnati have truly played like 3-1 teams or close to it, while Chicago and Miami have been more like 2-2 ... and Tennessee has been more like 1-3. In terms of SRS, the Titans grade out worse than the 1-3 Colts. In DVOA, they are 24th, behind five one-win teams.

Efficiency is the most direct path toward sustainable success, and the Titans ... have not followed that path. The Titans have been drastically less efficient than their opponents, and they have dealt with some field position advantages as well. The only ways they have been better than their opponents have been in red zone performance and turnover avoidance (in terms of both actual and expected turnovers).

No take-backs, of course. If the Titans’ offense improves as Mariota gets closer to full-strength, then Tennessee could theoretically improve overall, which could allow them to keep winning even if the close-game fortune fades. And this good fortune has allowed them to remain tied with Jacksonville for first in the AFC South a quarter of the way through the season. Even if the Jags pull ahead, Tennessee could still be long involved in the wild card race — go .500 the rest of the way, and you’re 9-7.

Still, the fundamentals desperately need to improve. Vrabel probably knows this as well as anyone, no matter how solid his defense is, and no matter how naturally Tresselian he and his team have proven to be.