COLLEGE STATION, Texas -- Some of Texas A&M defensive coordinator John Chavis' most enduring lessons didn't come on a football field, but rather on a tractor while growing up in Dillon, South Carolina.

His parents, Robert Jr. and Becky Jane Chavis, were Cherokee sharecroppers, and Chavis -- one of 10 children in the family -- learned at an early age the importance of earning his keep and doing things the right way. The family squeezed into a small house on the landowner's property before Chavis' father saved enough money to buy his own home. They mostly grew tobacco, but there were also other crops to be planted out of season.

"I can still remember my dad saying when we'd be planting whatever we were planting at that time that if one little spot was crooked, that he was going to wear my rear end out," Chavis recalled fondly. "To him, it wasn't just planting the rows. They had to be straight, or it wasn't good enough."

Just as important in the elder Chavis' eyes was the premise that the only job that mattered was the one you were doing right then.

"He was a farmer and not the most educated man, but he taught me a lot, how to fish and how to hunt. The most important thing he taught me, though, was how to work," Chavis said. "The best job is the one you've got, and you've got to take the right kind of pride in that job to make it that way.

"If you're always looking around, then you're not doing what you need to do to do your job right."

Despite a hiccup against Tennessee, John Chavis has made Texas A&M's defense into a force to be reckoned with. Courtesy of Texas A&M Athletics

In a world where coaches chase jobs the way most neighborhood dogs chase the ice cream truck, Chavis is the refreshing exception. He has been the quintessential grinder, coaching at just three schools since he returned to his alma mater, Tennessee, in 1989 as a defensive line coach.

It's not like he hasn't had chances to move around, either. He has turned down job interviews for head coaching gigs as well as NFL opportunities in the past. And, had it not been for his distrust of the LSU administration and his suspicion that Les Miles would eventually be forced out, Chavis probably never would have left LSU.

"Coach Miles is a good man and good coach. He was never the reason I left there," Chavis said.

So here he is at Texas A&M, a year and a half into one of his greatest challenges yet -- resurrecting an Aggie defense that was beaten down, beaten up and floundering near the bottom of the SEC in most defensive categories when Chavis arrived prior to the 2015 season.

"We always felt like we had the talent, but that something was missing," Texas A&M junior safety Armani Watts said. "Coach Chavis was that missing piece, the way he came in here and made us believe. We took on his personality on defense, that we're going to be the ones to set the tone."

Texas A&M coach Kevin Sumlin had already decided a few things needed to change in Aggieland if they were going to survive in the SEC's rugged Western Division. He knew bringing in Chavis, known as "Chief" to most around the college football world, would go a long way toward making Texas A&M a tougher, more physical football team -- and not just on defense. Plus, Sumlin had grown weary of competing against Chavis, especially seeing the way he shut down Johnny Manziel and the Aggies for two straight seasons in 2012 and 2013. During Manziel's Heisman-winning 2012 season, the Tigers picked him off three times and held him to 27 rushing yards in a 24-19 LSU win.

"We've always had confidence offensively, the way we've done things," Sumlin said. "Our defense was something that needed to not only change schematically, but to get some confidence and some pride. What (Chavis) has brought is an attitude that really started with our defensive players, giving them a reference point, or a standard rather, of what the defense should look like, and what the expectations are defensively, and he's held them to that standard."

The No. 6 Aggies face their biggest test of the season Saturday at No. 1 Alabama, which has won three straight in the series (averaging 49.6 points in those three games) since losing in the Aggies' debut SEC season in 2012.

There are telltale signs Chavis has Texas A&M's defense on the right track despite the Aggies giving up 684 yards, the most in school history, two weeks ago to Tennessee in a 45-38 double-overtime win. They are tied for second nationally in forced turnovers (17), third in tackles for loss (58), fourth in red zone defense (11 touchdowns in 26 red zone attempts), 13th in sacks (20), 22nd in scoring defense (19.2 points per game) and 28th in third-down defense (.340).

With its back to the goal line, Texas A&M has been excellent. The Aggies played 18 snaps of defense inside their own 10 against Arkansas and gave up just 17 points in those 18 plays. They've allowed just 13 touchdowns in six games, and five came against Tennessee. But even against the Vols, the Aggies came up with seven turnovers, including Watts' interception in the second overtime to seal the win.

"Coach Chavis was that missing piece, the way he came in here and made us believe. We took on his personality on defense, that we're going to be the ones to set the tone." Texas A&M safety Armani Watts

Even with defenses playing more plays than ever now because of all the teams utilizing tempo on offense, Chavis admittedly is still old school. One of his more legendary qualities is his stubbornness, and he's simply not ready to change his standards.

If an offense scores more than 17 points or gains more than 300 yards against one of his defenses, Chavis is still going to be ornery, even in a win.

"Maybe I'm not living in reality, but I'm not going to change," Chavis said. "Offenses have changed so much and are scoring so much. It's definitely a different feel, but then you look at the film, see things you can correct and feel a little bit better about it. I don't know if what constitutes good defense has changed or not. I just know that you're not going to win a championship unless you can stop people. Name me a team that wasn't good on defense that has won a championship. You can't."

Indeed, only once since the start of the BCS era in 1998 has a team won a national championship and finished outside the top 30 nationally in scoring defense. The lone exception was Auburn in 2010. The Tigers finished 53rd that season in scoring defense, allowing an average of 24.1 points per game, but also had a guy named Cam Newton at quarterback.

Perhaps the statistic that best puts into perspective what Chavis has meant to Texas A&M is how seldom it has given up 30 or more points on his watch. That was once a given in Aggieland, where winning a shootout was about the only way to win against a quality team. The Aggies yielded 30-plus points in half of their games (13 of 26) in the 2013 and 2014 seasons before Chavis arrived.

But in Chavis' first 19 games, it has happened only twice, and one doesn't really count because quarterback Kyle Allen threw three pick-sixes last season in a 41-23 loss to Alabama. The only other time came two weeks ago against Tennessee.

"We haven't arrived, but we're further along," Chavis said. "The numbers may not be as good as last year. I'm not sure, but I can tell you our players are more confident in what we're doing, and they really, really want to be good. They care about each other, and they're all buying into what we're doing and the philosophy of this team."

He isn't the only star, but Myles Garrett is the brightest one getting a chance to shine for Chavis. Matthew Emmons/USA TODAY Sports

One of the assurances Chavis got from Sumlin before taking the job was that the Aggies would practice in such a way that would allow the defense to develop and keep an edge. Privately, just about all defensive coordinators curse the spread/tempo offense because of the lack of physicality in practices.

"That has really bled over into what we want to do," Sumlin said. "We've changed a little bit philosophically offensively, obviously, to practice into that style and try to create a more physical football team. It started on defense. What we've tried to do across the board is continue that aggressive style and physical style, and I think it's permeated throughout the football team."

Whether he likes it or not, Chavis' $1.6 million annual salary makes him a rock star among defensive coordinators. Of course, that doesn't mean Chavis has to act the part. He's not big on publicity and has never been one of those coordinators constantly angling for a head coaching job.

"I guess I always cared more about winning than I did about being a head coach," Chavis said.

When he was at Tennessee, he interviewed for the Middle Tennessee State head coaching job and turned down an opportunity to interview for the Army head job. He also briefly took a job on Dom Capers' staff with the NFL's Houston Texans but changed his mind the next day. During his time at Tennessee and LSU, he had inquiries from everybody from Georgia to South Carolina to Texas about their open defensive coordinator positions. And when Miles hired Chavis prior to the 2009 season at LSU, the Mad Hatter had to beat Dabo Swinney and Clemson to the punch.

"When you start talking about the two best defensive coordinators in college football over the last 20 years, there are only two names -- Bud Foster and John Chavis," said Auburn defensive coordinator Kevin Steele, who grew up with Chavis and also played football with him at Tennessee. "Sometimes guys are hot for a while and then sort of fizzle out, but not Chief. His consistency is remarkable, and it's why so many of the top programs have come after him."

"Name me a team that wasn't good on defense that has won a championship. You can't." Texas A&M defensive coordinator John Chavis

The scars from being ousted at his alma mater when Phillip Fulmer and his staff were fired following the 2008 season are still there, but it doesn't define his tenure in Knoxville.

"It took a little while to get over that. It really did," said Chavis, whose defense that final season at Tennessee was ranked No. 1 in the SEC and No. 3 nationally. "But if you don't heal, then you're going to die. The memories I have at Tennessee aren't defined by what happened that last season by any stretch of the imagination. We accomplished a lot of things, and a lot of young men who came through that program are young men I still love and care about.

"But with eight years to look back on it, it was the best thing that ever happened to me. I was never going to leave Tennessee and had gotten too comfortable there."

Chavis, who turned 60 earlier this month, is bearing down on his 40th year in coaching. He's plenty comfortable in College Station, and any time the subject of how much longer he wants to coach is brought up, Chavis references something one of his favorite players once shared with him.

Al Wilson, the heart and soul of the Vols' 1998 national championship team, said, "Chief, you'll never know what you did for me. I never thought I could be that good. You made me believe that I could be that good," Chavis recalled.

Wilson went on to become a Pro Bowl linebacker with the Denver Broncos, and his words have stuck with Chavis.

"It's the best compliment I've ever had," Chavis said. "It was humbling to hear him say that and to know that you had that kind of influence on a young man. As long as I can keep having that same kind of influence on the young men here at Texas A&M, I'll keep doing what I'm doing."

And rest assured that he'll do it his way, the right way, and that all of the rows will be straight.