Will Muschamp’s second stint as Auburn’s defensive coordinator in 2015 was not a good one. Last season, the Tigers allowed 222.6 passing yards per game to rank just 11th in the SEC.

They were better at preventing passing TDs, surrendering 13 to rank fifth in the conference. And Auburn surrendered more than 300 passing yards to just three opponents: Kentucky, Idaho – yes, Idaho – and Ole Miss, which burned a lot of teams thanks to Chad Kelly, arguably the best QB in the conference.

Here is how the Tigers’ passing defense performed in some key categories in 2015:

Passing yards allowed per game: 222.6 (11th in the SEC)
Most yards allowed: 402, Ole Miss
Passing TDs allowed: 13 (5th)
300-yard passers allowed: 2

Kevin Steele, LSU’s defensive coordinator last year, takes over for Muschamp with the obvious intention of improving upon those numbers. Coincidentally, under Steele in 2015, the Bayou Bengals were 12th in the SEC in passing yards allowed (224.3) and were also worse than Auburn with 22 passing TDs allowed, ahead of only the Rebels’ conference-worst 23.

Pass-rush

The most important returnee in this department is defensive end Carl Lawson, who will be back for his junior season. He has All-SEC and All-American potential, but he has to stay healthy. An early season hip injury limited him to just seven games in 2015.

The Tigers get another boost with the return of Montravius Adams, who passed on the NFL Draft. Fellow defensive tackle Dontavius Russell, who is coming off a solid season, is also back. JUCO transfer Paul James and incoming recruit and fellow early enrollee Marlon Davidson should bolster the defensive line as well.

Auburn’s linebacking depth will take a hit with starters Kris Frost, Cassanova McKinzy and Justin Garrett all gone. But the Tigers are counting on Tre’ Williams and Illinois transfer T.J. Neal to make up for those losses.

Steele more than likely will use two linebackers and deploy a hybrid LB/safety when Auburn takes on spread squads such as Texas A&M, Mississippi State and Ole Miss. Regarding Auburn’s base defense, expect multiple schemes – a 4-3 alignment and some 4-2-5. Plus, Steele might stand up some ends and linebackers.

Sack artist

Despite his injury-marred college career, Lawson is still Auburn’s most feared pass-rusher. He will line up at end opposite Byron Cowart, with Adams and Russell manning the tackle spots.

At 6-foot-2 and 253 pounds, Lawson already has an NFL-ready build. He uses his hands extremely well to shed offensive linemen and also has an explosive first step that helps him to get into backfields quickly.

Lawson also boasts a smooth swim move, and he has experience playing in a two-point and three-point stance. His non-stop motor and hard-nosed playing style are also other positives.

The Alpharetta, Ga. native definitely has traits that will help him this season, but his biggest question marks are a lack of experience, productivity and health. Because of those factors, the jury is still out on whether he can be a consistent tackler, but Auburn would accept the flashes of brilliance Lawson showed as a freshman, when he had 7.5 tackles for loss, including 4 sacks.

Entering the 2016 season, Lawson’s impact on the Tigers’ defense can’t be underestimated. In the seven games Lawson played last year, Auburn surrendered 55.1 fewer yards and 8.7 fewer points per contest than it did in its other six contests, according to ESPN. Anything less than 12 games and 10 sacks from Lawson this year would be a disappointment.

Ball in the air

Steele has the luxury of building his secondary around cornerback Carlton Davis, who made the All-SEC freshman team last season and seems primed to become an all-conference first-teamer. The leading candidate to play opposite Davis is Ohio State transfer Jamel Dean.

Dean sat out last season as a transfer while rehabbing a knee injury that prompted the Buckeyes to move on from him and turn to other players. Dean, who has no in-game experience, emerged during spring ball for Auburn.

Stephen Roberts, who appeared in all 13 games last season, could start at strong safety this year. His is coming off a sophomore season with 26 tackles and 3 pass breakups, with most of that production coming over his last five contests of the year.

After missing the early part of spring practice with an undisclosed illness, Rudy Ford stepped right back into the starting lineup at free safety. Auburn’s leading tackler the last two seasons, Ford will be counted on to keep making stops while providing senior leadership.

When Auburn goes to the 4-2-5, Ford will slide over to the nickel back spot, with Nick Ruffin taking over at free safety. Despite being benched for four games last season, the 6-foot, 203-pounder finished with 27 tackles and 4 pass breakups.

Pickoff artist

Davis is Auburn’s top cover guy, and that reputation goes beyond his team-leading three interceptions last season. He and Ford are Auburn’s most physical defensive backs, and Steele will be counting on their toughness when the Tigers need to shut opponents down.

Auburn is hoping that Davis can avoid further off-the-field incidents. If Davis stays injury- and trouble-free, all-conference first-team honors should be well within his reach.

Greatest concern

Auburn’s biggest worry could be a potential lack of depth in the secondary. Three potential reserves are coming off injuries.

T.J. Davis is recovering from a torn ACL, as is fellow defensive back Josh Holsey. Meanwhile, Tray Matthews missed all of spring camp after having offseason shoulder surgery.

One stat that must change in 2016

Auburn has to get better at defending against the pass on third down. In those situations in 2015, the Tigers finished 11th in opponent passer rating, and they allowed foes to convert 41 first downs. Only two other SEC teams surrendered more.

Auburn goes into 2016 with legitimate questions about its pass defense. For starters, will Steele be an upgrade over Muschamp? The knee-jerk reaction is to say yes, but the Tigers need to address other ifs.

Will Lawson stay healthy and can he replicate — or improve upon — his freshman success? That’s one of the biggest questions of the year, but the Tigers have a decent number of returnees on their defensive line and in their secondary, and their experience should be what helps Steele improve upon a disappointing 2015 season.