Editor’s note: This is the 4th in a series previewing every SEC West team’s defense. Next: Mississippi State.

The LSU defense didn’t always play like a championship defense in 2019.

But it improved as the season went along and it played its best when the competition was the toughest and the stakes were the highest during the 15-0 Tigers’ championship run.

Now the defense is starting over – much like the entire team.

Dave Aranda left to become head coach at Baylor, and former Nebraska and Youngstown State head coach Bo Pelini (above) returned to Baton Rouge for his second stint as LSU defensive coordinator.

Pelini, who helped the Tigers win a BCS Championship after the 2007 season to complete his previous 3-year stint, will employ a base 4-3 scheme rather than the 3-4 used mostly by Aranda.

It’s not exactly an overhaul of the scheme. The most noticeable change will be an outside pass rusher operating from a two-point stance rather than a three-point stance.

Pelini will have to work without several key players from last year’s team, including the entire starting linebacking corps. Patrick Queen, Michael Divinity Jr., Jacob Phillips and K’Lavon Chaisson have moved on, as have defensive linemen Rashard Lawrence and Breiden Fehoko as well as defensive backs Grant Delpit and Kristian Fulton.

That’s a lot of talent gone from a unit that bounced back from late-season struggles against Alabama and Ole Miss to play much better against Texas A&M in the regular-season finale, Georgia in the SEC Championship Game, Oklahoma in the CFP semifinals and Clemson in the CFP Championship Game.

It’s a new season with a new coordinator and a whole bunch of new starters. But LSU always expects to play championship-caliber defense and the 2020 season will be no exception to that.

Will they be better in 2020? Let’s take a look.

Personnel

Pelini’s arrival coincides with LSU having its best defensive line depth in a few years. That’s not why head coach Ed Orgeron hired him, but it is useful for Pelini’s 4-3 scheme.

The strength of the line figures to be in the middle with tackles Tyler Shelvin, Apu Ika, Glen Logan and Neil Farrell Jr. That’s size, talent, experience and depth.

Former tight end TK McLendon and Justin Thomas are the likely ends, backed up former linebacker Andre Anthony and highly-regarded freshman BJ Ojulari. That’s less experience than the tackles have, but not necessarily less talent.

Damone Clark has been a dependable backup and now is expected to be a leader on the rebuilt linebacker corps as he starts in the middle after being the team’s sixth-leading tackler last season. Ray Thornton and Micah Baskerville are returnees that will have an impact on the outside.

The unit received a boost when former FCS All-American Jabril Cox arrived from North Dakota as a graduate transfer. Pelini is familiar with Cox after coaching against him while at Youngstown State, and Orgeron said he expects Cox to be an impact player.

The school that likes to be called “DBU” should enhance that reputation this season.

The Tigers’ offseason was defined by numerous early departures to the NFL, but LSU got a big boost when strong safety JaCoby Stevens decided to return for his senior season. Stevens was the team’s 2nd-leading tackler a year ago and his ability to make plays in the backfield, the secondary and in between should allow him to handle a role similar to the one Delpit vacated after two exceptional seasons.

Stevens has plenty of talent around him with super sophomore Derek Stingley Jr., sophomore Cordale Flott, junior Todd Harris, senior Kary Vincent Jr. and freshman Elias Ricks.

Pressuring the QB

The defensive line should set the tone for the pass rush more under Pelini than it did under Aranda. The Tigers will be more aggressive up front than they were last season.

Aranda often counted on his 3 linemen to provide the pass rush without seeing significant results. Farrell led the group with 3.0 sacks. When he turned loose linebackers and defensive backs, the Tigers had more success getting pressure. Fittingly, Chaisson led the Tigers last season with 6.5 sacks and Stevens was 2nd with 5.0.

Pelini will count on his 4 linemen to get into the backfield regardless of down and distance. Orgeron has spoken highly of Olujari and the true freshman will have an opportunity to be a top pass rusher right away.

Stevens’ versatility will lead the pass rush from the back 7 when Pelini decides to supplement the push from the front.

Run defense

LSU is typically stout against the run. Only once in the past 5 seasons have opponents averaged more than 130 yards rushing against the Tigers.

The depth at tackle should be a good starting point for slowing down opposing run games in 2020, too.

Stevens will be one of the leading tacklers and Pelini expects Clark to take on a leading tackler role such as Phillips and Queen did last season and Devin White did before them.

The Tigers don’t have much experienced depth among the linebacker so 4-star recruits Antoine Sampah and Philip Webb have a chance to have an impact at a position that requires the use of two units.

Pass defense

Stingley was a freshman All-American after leading the SEC with 6 interceptions last season. He again should be one of the top defensive backs in the country, and Flott and Ricks add more elite talent to the cornerback position.

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Throw in Stevens, Harris and Vincent and the secondary has the most experience and depth on the defense.

After sharing the SEC lead with 17 interceptions last season, DBU once again should have one of the best secondaries in the SEC if not the entire country.

Special teams

Punting was little more than an afterthought for last year’s team. Only 3 Power 5 times punted fewer times per game than the Tigers, but Zach Von Rosenberg is nonetheless experienced and effective. He didn’t punt enough to qualify for the SEC leaderboard, but he averaged 42.8 yards per attempt. The Tigers only allowed 9 returns in 15 games.

With the offense and the defense going through growing pains with younger starters, field position will become more important this season and Rosenberg is capable of contributing to that with his placement ability.

Overall

The defense will be better than it was last season.

Improving on the performance during the first 2/3 of last season isn’t that big a challenge, but matching the play of last year’s defense down the stretch and surpassing its year-long performance is a greater challenge.

Aranda’s scheme was more sophisticated than most, which periodically contributed to breakdowns. DeVonta Smith caught Stingley still receiving instructions from the sideline and raced past him on one notable TD pass.

Pelini’s scheme is simpler, which should be helpful to a talented and mostly inexperienced group.

Like last year’s defense, this year’s should be playing its best at the end of the season.