Detroit Lions 2025 training camp preview: How Alim McNeill’s injury impacts DT room

The next installment in our training camp preview series looks at the Detroit Lions’ defensive tackle group.

In this installment of our Detroit Lions 2025 training camp preview series, we switch sides of the ball and examine the Lions’ interior defensive line group, speculating on current and future roles, and discussing how many players from this group could make the 53-man roster.

Previous training camp previews:

• QB: Can Hendon Hooker stick at QB2?
• RB: Will there be any changes to the room?
• WR: Loaded with depth options and youth
• TE: Who will win the TE3 job?
• OT: All eyes on Giovanni Manu
• IOL: What to expect from IOL overhaul

Setting the table

The Lions entered 2024 with an improved group of interior defensive linemen, led by Alim McNeill (who received a contract extension mid-season ), DJ Reader (who was coming off a hip injury), and Levi Onwuzurike (a hybrid defender who split time inside and on the edge), with rookie Mekhi Wingo and veteran Kyle Peko rounding out the room.

Unfortunately, injuries at defensive tackle dominated the headlines. Brodric Martin started the season on injured reserve, and although he returned, it was in a limited manner. Peko landed on injured reserve early in the season and was replaced by veteran Pat O’Connor. But the biggest blow came in December when McNeill tore his ACL. With their depth exhausted, the Lions turned to practice squad players Chris Smith, Myles Adams (via Seattle), and Jonah Williams (via Rams) to finish off the season.

Entering the offseason, the Lions knew that they would need to invest heavily at defensive tackle in order to overcome the absence of McNeill—who is expected to miss time during the regular season —while also planning for the future.

That led to arguably the Lions’ biggest move of the offseason, when Detroit selected Tyleik Williams in the first round of the NFL Draft. Williams joined McNeill, Reader, Wingo, and Martin, who were all still under contract. But the Lions weren’t content to stay put, as they re-signed Onwuzurike , O’Connor , Adams , and Smith (futures) to one-year contracts. Additionally, the team signed Roy Lopez to a one-year deal in free agency and Raequan Williams after a tryout at rookie minicamp . Peko remains an unrestricted free agent, while Jonah Williams signed with the Saints .

Roster construction

Under the Brad Holmes and Dan Campbell regime, the Lions have deployed different styles of defensive front, but they’ve remained consistent in maintaining the number of players they’ve dedicated to the position.

Let’s take a look at what they’ve done on the interior defensive line in the previous four seasons:

• 2021: With a two-gapping look with three starting interior defenders, the Lions initially kept seven interior defenders (including three hybrid players) and ended with seven.
• 2022: When the front shifted to a 4-3, the Lions reduced their number to five (with one hybrid) and also ended the season with five players.
• 2023: The Lions would repeat their previous season’s strategy by opening with five interior defenders (with one hybrid), while also closing with five on the roster.
• 2024: Rinse and repeat the previous two seasons: Open and close with five interior defenders (including two hybrids).

Gap-and-a-half

The Lions deploy a “gap-and-a-half” defensive front, which best features their players’ strengths while maintaining the overall philosophy of prioritizing stopping the run. In base sets, they deploy a standard 3-technique and a nose tackle to pair with their defensive ends. However, when the Lions put a SAM linebacker on the field, they pinch their nose tackle, and ask one of their defensive ends to kick to a 4i, which is why hybrid players like Onwuzurike and Wingo (along with defensive ends like Josh Paschal) become so valuable.

Here’s an example of the Lions’ “Base” defense:

And here’s a look at how they adapt to adding a SAM:

Essentially, the Lions ask their nose tackles to play both the 0T and 1T, others to alternate between the 3T and 1T, and a third hybrid player to have the range to play between the 3T and 4i.

The battleground

Heading into training camp, the Lions have a few questions that need to be answered, but none looms larger than McNeill’s injury.

How long will McNeill be sidelined?

While there has been no definitive return date yet, coach Dan Campbell has said he doesn’t expect McNeill to be available during training camp , and his rehabilitation will likely bleed into the season. How far into the season is unknown at this time, but the Lions do feel confident that McNeill will return at some point.

How will starting snaps be divided up in McNeill’s absence?

In an ideal world, the rookie Williams would step in right away at the 3T and play opposite Reader, who will start at nose tackle. After playing 3T at Ohio State, yet being asked to primarily stuff the run, he is uniquely skilled to play the role vacated by McNeill.

However, there are two potential hurdles to clear if Williams earns a starting role. First, asking a rookie to pick up all of McNeill’s snaps—which ranged between 75-85% of defensive snaps—is not realistic. And second, there’ll be an acclimation period that Williams will have to progress through, meaning they’ll likely need a veteran to supplement some of the workload.

Enter Onwuzurike. As the Lions’ best hybrid interior defender, Onwuzurike has the skill set to take snaps everywhere from the 1T to the Wide-9—though he typically isn’t asked to push inside further than the 3T. While the Lions prefer to keep Onwuzurike’s role fluid, he can certainly help fill a void as a starter while Williams settles in, regardless of what that timeframe is.

Beyond the presumed starters, what’s the rest of the depth chart look like?

After Reader, Williams, and Onwuzurike assume their roles, the Lions will still have plenty of reserve snaps available for whichever depth players earn roles. While the Lions have only kept five interior defensive linemen the past three seasons, McNeill’s injury could result in them carrying six this season.

• Roy Lopez, NT: One of the Lions’ priority free agent signings, Lopez brings starting nose tackle experience to Detroit’s front. While he’s unlikely to unseat Reader for a starting role, Lopez could still see a significant amount of snaps. Depending on how often the Lions want to deploy a nose tackle, the combination of Reader and Lopez should ensure the defense is never without the option.
• Mekhi Wingo, 3T/4i: Like Onwuzurike, Wingo brings a hybrid element to his game that the Lions covet in order to run their scheme seamlessly. If Onwuzurike spends the early parts of the season in the McNeill role while Williams acclimates, there’s an opportunity for Wingo to increase his snaps by acquiring more hybrid reps. There’s a lot to like about Wingo’s game, and with Onwuzurike (and Paschal) in a contract year, this could be a big developmental season for his future.
• Pat O’Connor, NT/3T: O’Connor entered the NFL as a “big” defensive end, then shifted to a hybrid player role in Tampa Bay, where he spent five seasons learning under Kacy Rodgers, the Lions’ new defensive line coach. Last season, O’Connor found the field, mainly as a reserve nose tackle and 3T, but with his old coach now in Detroit, it’s fair to wonder if his role will expand this season.
• Brodric Martin, NT: Entering his third season in Detroit, Martin may be at a tipping point in his career. While blessed with impressive size (6-foot-5, 330 pounds), he’s only played in five games and seen 53 defensive snaps in his NFL career. And the reason for the limited opportunities is no secret: pad level. For the past two seasons, when any Lions coach was asked about Martin’s progress, every single one of them mentioned “pad level” as the main issue holding him back. We’ve seen several Lions players make third-year jumps in the past, and if he can figure out his pad level, he could be the next player to pull off this accomplishment.
• Chris Smith, 3T/NT: A 2023 UDFA, Smith has spent the majority of his time in Detroit on the practice squad, but he found the field for five games (47 snaps) in 2024 and regularly gets praise from coaches—mainly centered around his work ethic. While he lacks Martin’s imposing frame, he’s a terrific athlete and works his tail off. And in Detroit, that’ll get you an opportunity to play.
• Myles Adams, 3T/4i: Acquired by the Lions in Week 12 of last season, Adams’ intelligence got him opportunities on the field (91 snaps over five games) and earned him a second contract. Adams played mainly inside at the 3T in Detroit last season, but he’s experienced at the 4i and can bring some hybrid depth to the line.
• Raequan Williams, 3T/4i: The former Michigan State Spartan bounced around the league the last four seasons, and while he wasn’t on a roster in 2024, he impressed Lions coaches enough during his tryout at rookie minicamp to earn a spot on the training camp roster. Williams seems like a longshot to make the 53-man roster, but we said the same thing about Peko at this time last season, and he earned a spot.