As complex and granular as NFL strategy is, the biggest discussion around football tactics right now centers around matching up big people against smaller people.

Last week, Fox color analyst Greg Olsen brought up how the Seahawks are creating explosive plays by forcing teams to bring their base personnel on the field (only four defensive backs) to create mismatches in the passing game and how defenses might respond by basing their personnel groupings on down and distance rather than matching what groupings the offense is putting on the field.

I spoke to two defensive coordinators and two defensive coaches about their philosophies on matching personnel and the reasons why they match or don’t match. While defenses definitely are trending toward playing the down and distance rather than matching, teams have different philosophies about how to handle the cat-and-mouse games.

This week provided the perfect matchup to examine as the Seahawks played the Rams. Rams defensive coordinator Chris Shula is doing one of the best coaching jobs this season and is leading a unit that has improved to second in DVOA, FTN’s efficiency metric that accounts for strength of schedule. The Rams played more sub personnel (five or more defensive backs) against the Seahawks than any team this season, resulting in the Seahawks’ worst offensive performance this season. Will this be a trend moving forward, or just with how teams play Seattle?

Terms to know:

Sub: Nickel (five defensive backs) or Dime (six defensive backs) personnel

Base: Four defensive backs with any combination of seven defensive linemen or linebackers

Heavy personnel: Multiple tight end or back sets

11 personnel: 1 back, 1 tight end, 3 receivers

12 personnel: 1 back, 2 tight ends, 2 receivers

13 personnel: 1 back, 3 tight ends, 1 receiver

21 personnel: 2 backs, 1 tight end, 2 receivers

Shoutout to @PFF_Moo for putting this chart ranking teams by how much they mismatch against heavy and light personnel groupings pic.twitter.com/cVwSLB15fQ

— Ted Nguyen (@FB_FilmAnalysis) November 18, 2025

This chart, created by Pro Football Focus’ Timo Riske, shows how much teams “mismatch” personnel (play sub against heavy personnel or base against three-receiver sets) outside of the red zone. The list is sorted by which teams mismatch the most from top to bottom. The Raiders are ranked at the top because they use former safety Jamal Adams at linebacker.

The dark green bar shows how much base personnel the defense plays against 11 personnel, and the dark orange bar shows how much sub personnel defenses play against heavy personnel.

The Seahawks and Ravens are two of the top teams that mismatch, but they have the personnel to do it because they have defensive backs that can play the run like linebackers. Teams like the Bills, Bengals and Commanders want to play sub against heavy personnel, but they get gashed against the run because they don’t have the personnel to play the run with light bodies. Obviously, the solution isn’t simply to stay in sub personnel to remain sound against the pass no matter what, the game is more complicated than that. Here are factors that some of the best defensive teams in the league consider when matching or mismatching.

What type of offense are you playing?

“The No. 1 thing is, if you want to put nickel out there to a bigger personnel, can you stop a run in that? Or are they willing to stick with the run?” an NFC defensive coordinator said.

Defenses that want to play sub don’t necessarily have to stop the run. They just have to slow it down and not allow explosive runs. Even if a team is running for four yards a carry, there are play callers who could get impatient and go away from it.

“I think it’s really just like the risk management based on which is the most tough to defend in your smaller or bigger grouping,” an AFC defensive coordinator said.

Understanding what your personal groupings can defend and what kind of threats certain offensive groupings present is key. The Seahawks were among the most inconsistent running teams in the league, yet defenses kept matching their heavy groupings with base and allowing them to create bad matchups in the passing game. The Rams played 35 snaps of sub personnel (19 nickel and 14 dime) against the Seahawks between the 20-yard lines, which is the most the Seahawks have faced all season, according to ESPN’s Benjamin Solak.

11:29 remaining in the first quarter, second-and-2

Here, the Seahawks came out in 12 personnel. The Rams mismatched with their nickel personnel. Both of Seattle’s tight ends lined up to one side and were flanked by a receiver, creating a three-man surface. You can see the bubble they are trying to create with this formation, which the Rams responded to by lining up both their inside linebackers over the bubble.

On the other side, safety Quentin Lake played in the box as a linebacker.

Linebacker Omar Speights did a good job of filling his gap and Lake was able to scrape over and make a tackle on running back Kenneth Walker.

Lake didn’t put a big hit on Walker and the Seahawks got a four-yard gain out of the play, but the run wasn’t explosive and this is the type of gain that the Rams defense could live with. Modern defenses want to force offenses to chip away. The Rams were able to create a turnover on the next play.

11:05 remaining in the first quarter, first-and-10

On this play, the Seahawks were once again in 12 personnel. On first-and-10, a running down, the Rams remained in nickel. They even kept both safeties back. Lake was on the line of scrimmage and formed a 6-1 front, which is difficult to run outside zone against.

The Seahawks had a pass called. The Rams played cover 1 (man-to-man with a deep safety) with a disguise. After the snap, safety Kamren Kinchens (highlighted) rotated down and played robber (help on in-breaking routes).

Quarterback Sam Darnold had no idea Kinchens rotated down and he threw an interception right to him. Though this wasn’t the most complicated defensive disguise, the Rams wouldn’t have been able to get to it out of base because a safety would have had to come down to cover the slot if there wasn’t a nickel on the field. It’s levels above what the Seahawks would typically get when defenses play base and simplify against their 12 personnel.

The Rams picked off Darnold four times and held the Seahawks to a 6.3 percent explosive play rate, their lowest of the season. Against the Rams’ sub personnel groupings, the Seahawks only had a 44 percent rushing success rate.

Also, defenses have to consider what pass concepts offenses will run from their heavy personnel packages. Not every offensive coordinator is adept at creating advantages from different personnel groupings. One defensive coordinator said that if a team is just running two-man routes with their play-action game, you should be able to cover those types of plays from your base personnel the same way you could from sub. The 49ers’ Kyle Shanahan gets extremely creative with how he takes advantage of mismatches, so it’s a lot harder to have the right or wrong answer when you match or mismatch against them.

“It’s what the Niners have done for years,” the AFC defensive coordinator said. “They just get into their 21 package and they just morph into anything formationally. It’s not just like play-action explosives; they’re running any type of play with all those guys. They’ve done that forever. You have to know the ability of the coordinator to match whatever they’re doing to attack your system.”

CMC TD 🙌

SFvsLAR on Prime Video
Also streaming on @NFLPlus pic.twitter.com/OMz2ecO7Gq

— NFL (@NFL) October 3, 2025

Despite what personnel a team can put on the field, the play caller is a big determinant in how long defensive coordinators can get away with mismatching.

Don’t be predictable

“I would think it just continues to trend more and more towards playing the situation based on the down and distance and field position, but most offensive coordinators are smart enough, if they know whatever direction you go, they’re gonna pivot the other way,” the AFC defensive coordinator said.

Some defenses will mismatch to give the offense a different look and skew the analytics. One defensive coach said they actually want to dictate to the offense what to do with their personnel.

“For us, we get played very differently than kind of teams might play throughout the year, so a lot of teams’ tendencies over the course of the year don’t hold true against us when they play us,” a defensive coach said. “We don’t get a whole lot of like 11, especially on early down. So we try to dictate the terms defensively rather than let the offense dictate terms.”

One way a defense can prevent a defense from dictating to them what personnel grouping to be in is to ensure they are versatile from a coverage perspective in each of their personnel groupings. Some offenses, like the Rams, want to get defenses into base by getting into 13 personnel because the coverage menu for most defenses is much simpler and smaller; however, the better defenses in the league are expanding what they can do out of base.

If you go back to the chart above, you’ll find innovative defensive coordinators like Shula, Vic Fangio, Jesse Minter, and Jeff Hafley mismatch below the league average. They can do this because they intentionally designed their base packages to be versatile, so offenses can’t force them to be simple, simply by putting heavy personnel on the field.

Expand what you can do in base!

“I’ve tried to make our base system as multiple as possible, so I think we’re less predictable than some teams,” the NFC defensive coordinator said.

Many teams can get creative with mixing their coverages and disguises from sub, but most defenses don’t want to ask their sam (strong-side) linebacker to do too much in coverage. Some offenses can use formations and motions to get that sam linebacker — who would typically get replaced by a nickel — to have to run downfield with a receiver. In a 3-4 defense, that sam linebacker could actually be an edge rusher. Depending on the offense, that could be an acceptable risk for some defensive coordinators.

“Those guys are hand-on-hand combat every play,” one defensive coach said. “And so to do that and then ask them to go, ‘Hey, I’m going to go out here and (cover) a No. 2 (receiver)’, it’s pretty tough. So you wanna be somewhat limited, but obviously you don’t wanna handcuff yourself either,” one defensive coach said.

This is what makes versatile players like Vikings linebacker Andrew Van Ginkel so valuable. Van Ginkel can line up on the edge in base, but he can also play so many more coverage techniques and assignments than a typical edge player.

The Eagles have inside linebackers Zack Baun and Jihaad Campbell, who both can play off-ball, line up on the edge, and drop into coverage. Eagles defensive coordinator Vic Fangio does an excellent job of utilizing their versatility.

Week 8, 6:10 remaining in the first quarter, first-and-10

On this play, the Eagles mismatched their base 3-4 front against the Giants’ 11 personnel. This personnel grouping is unique because they have three inside linebackers (Nakobe Dean, Campbell, Baun). All three inside linebackers can defend the run and cover. Initially, they had outside linebacker Jalyx Hunt lined up over the slot like he was going to cover, but right before the snap. Hunt moved inside to rush and Baun bumped out to cover.

The defense appeared to drop into a cover 2 zone in which the linebackers latched onto their assignments with man technique after the route distribution. This may not be a coverage that a lot of defensive coordinators are willing to play from base against 11 personnel, but it allowed the Eagles to be stout against a possible run while sound in coverage. Of course, they could only do this because of the versatility of their inside linebackers.

The importance of versatile players

“Nickels have to be able to play linebacker. Defensive backs like (the Rams’) Quentin Lake and Nick Emmanwori from Seattle,” the NFC coordinator said. “Those guys are big and they can align in the box and play in the core like a linebacker.”

The Lions play more base against 11 personnel than any other team, because they want to remain stout against the run with three linebackers against the run. Safety Brian Branch allows them to do that because, against 11 personnel, he can lock up slot receivers in man coverage.

Defensive coaches also talked about the value of defensive backs who not only can align in the box but also hold up against tight ends lining up on the edge. Ravens safety Kyle Hamilton is the prototype for this type of player. Playing on the edge is important because against multiple tight ends lined up on the same side, defenses want to close the bubble by bringing their defensive end inside. When that happens, someone must replace the edge defender.

3:56 remaining in the first quarter, second-and-3

Against a three-man surface (two tight ends and a receiver), Hamilton essentially lined up as an outside linebacker, allowing the defensive end next to him to line up inside the bubble.

Hamilton was able to shove the tight end in front of him into the backfield and eliminate the edge.

Obviously, these types of players don’t grow on trees, but there was a time that tweeners were looked at as a negative. Today, players who can play multiple positions without even being elite at one thing are extremely valuable against modern offenses.

As with everything, there is no simple answer, and everything is matchup- and personnel-dependent. What is clear is that defenses are moving away from simply matching personnel and are looking into many other factors when deciding on which personnel groupings to send out.