What Changes Could be Coming to the Vikings’ Defense?

At his end of March press conference, Vikings head coach Mike Zimmer said he will be making some changes to his defensive scheme - big and small - in order to change and adapt to the changes offenses have been making over the past four or five years, and also so they won’t have to install as many adjustments each week during the season in their game planning.

Of course he didn’t spell out what all the changes will be, for every opponent to know and plan for, but we can look for clues, based on what he did say, along with recent roster moves, as to what changes he may be planning to implement.

First, there are Zimmer’s relevant comments regarding defensive scheme change:

It’s been a really good offseason. You know we’ve had some coaching staff changes, and that’s been going really well, and then scheme-wise we’ve been going through everything with a fine-tooth comb, trying to evaluate every little thing that we’re doing, things that we can improve, things we’re doing terminology-wise, all the different areas... we’ve had some of the best meetings we’ve had in eight years probably, dissecting everything that we do, going through it, like I said before, with a fine tooth comb. I’ve been really impressed with the coaches that are in there, but also the offenses have changed so much in the last four or five years, it’s time that we need to do some things differently, and change, and adapt... the number one thing we wanna be doing on defense is we wanna play fast, we wanna play physical, and we don’t wanna be thinking. The offenses have been getting us to think lately- an adjust here, an adjust there, do this and do that, and you know some of these things we’ve talked about, and it’s just too hard to implement during the season. Some of it is big change, some of it is minor tweaks.

Secondly, there are the roster moves the team has made so far in free agency. The first, acquiring DT Dalvin Tomlinson, was acknowledged as the top priority for the Vikings by Rick Spielman. The Vikings have needed an upgrade at 3T since Sheldon Richardson, so it wasn’t surprising that 3T was a priority. But making the top priority a big 3T like Dalvin Tomlinson - essentially a NT with more athletic ability - may provide a clue into future changes.

Beyond Tomlinson, the Vikings were interested in, and acquired, cornerback MacKensie Alexander and safety Xavier Woods. Patrick Peterson was more of a surprise acquisition, or what Mike Zimmer called a lucky break. But upgrading an outside cornerback spot didn’t appear to be a top priority for the Vikings this off-season, but a chance to get Patrick Peterson back on track was too good an opportunity to pass up.

But going back to MacKensie Alexander, the Vikings already have three guys that’ve played slot cornerback on the roster. Jeff Gladney, Mike Hughes, and Harrison Hand. Nevertheless, they wanted to bring back Alexander. It’s true that Hughes has had injury issues and may not be part of the Vikings plans after this year, if not sooner, but how many slot cornerbacks do you need? Even if they part ways with Hughes, they still have three.

In addition to the slot corners, the Vikings had a hole to fill at safety, and lack depth at the position as well, so acquiring a Xavier Woods in free agency wasn’t a surprise. Mike Zimmer said he talked to Woods and told him he’s coming to a good situation for him with the Vikings. Asked if he’d play more free safety, Zimmer went on about his versatility and the roles he’s played at safety. The Vikings have also been in contact with some safety draft prospects as well. They’ve talked with, or attended pro days for Jacoby Stephens, Josh Bledsoe, Trevon Moehrig, Javon Holland, and Talanoa Hufanga. Again, not surprising given the lack of depth at the position, and Harrison Smith’s age, but another tidbit of information to add.

Lastly, Zimmer made some coaching changes on the defensive side as well, hiring his long-time acolyte Paul Guenther as a senior assistant, and Karl Scott as defensive backs coach. Scott served in the same position at Alabama the past three years, where they use pattern matching concepts as part of Nick Saban’s 4-2-5 defense. Paul Guenther implemented the pattern matching concepts while he was defensive coordinator for the Raiders.

So what conclusions could we draw from such a limited amount of information?

We know from his comments that Zimmer is planning a big change, and some smaller ‘tweaks’ in response to changing offenses over the past several years. He’s talked about using a third safety for years, and mentioned the possibility of using more DBs in his most recent press conference.

One possibility that would fit Zimmer’s comments and the players they’ve acquired is to go with a 4-2-5 as their base defense.

What is a 4-2-5 Defense?

At it’s most basic, a 4-2-5 defense is simply a nickel defense which most NFL defenses use most of the time - including Mike Zimmer. In Zimmer’s 4-3 scheme, it’s simply replacing a linebacker with a defensive back, typically a slot cornerback. It’s usually done in passing situations or when the offense has 3 wide receivers. But there is a broader, more complete scheme that operates with the same number of defensive linemen, linebackers, and defensive backs as well.

The origins of the 4-2-5 defense go back a long way, but the modern version is usually credited to Gary Patterson at TCU over ten years ago, and has since spread to many other college football teams, including Alabama, and among the pro ranks in New England and Seattle, which have used it at times.

Above is a standard alignment for a 4-2-5 defense. The numbers corresponding to the number of defensive linemen (4), linebackers (2), and defensive backs (5). The strong safety (SS) is aligned as an ‘overhang’ defender on one side of the box, and the Star (S) or nickelback is aligned on the other side. The star or nickelback defender is essentially another safety - someone who can cover but is also a good tackler and effective in run defense, and who can also be an effective blitzer.

Normally an opposing offense in a 2x2 formation, meaning 2 WR/TE/RB on either side of the formation, as shown here, may opt to run against this defensive formation, because with only six defenders in the box, versus six blockers, they have the advantage. Indeed, one of the more common trends among NFL offenses in recent years is to have a run or pass play option, depending on how many defenders are in the box pre-snap, along with down-and-distance considerations. Against a traditional nickel defense, the quarterback may focus on how the nickelback is aligned, in particular if they are positioned inside the box or not, and call a run or pass play based on that. Similarly, against a traditional 4-3 base defense, with a 3rd linebacker instead of a nickelback, a quarterback could option a pass where the F-back (as in Flex) runs a route with a linebacker in coverage, hoping to take advantage of a mismatch in coverage. Sometimes even a traditional tailback/fullback combination in the backfield can motion a good pass-catching tailback to the slot and take advantage of the linebacker-in-coverage mismatch. Having a nickelback or star defensive back eliminates the ability of an offense to take advantage of the linebacker mismatch.

But with the 4-2-5 defensive formation, there remains a perceived weakness against the run. This is where having two big, run stuffing interior linemen come into play - aka Michael Pierce and Dalvin Tomlinson. Those two linemen can combine to effectively control three of the four interior gaps, plugging those running lanes, while a linebacker can control the remaining one, the defensive ends the outside gaps, with one linebacker remaining to flow and fill as necessary. The two safety ‘overhang’ defenders can also provide run support against between-the-tackle runs, while being well positioned to disrupt outside runs or when the running back bounces outside after finding the interior plugged. Finally there is the free safety charging downhill in run support. The run defense mentality for the box and overhang defenders is an inside-out approach: looking first for inside runs, and that not being the case, flowing outside to defend perimeter runs.

Against the pass, the 4-2-5 has a few advantages. First, there are five defensive backs, which eliminates easy mismatches against a slower linebacker not as adept in coverage.

Secondly, the alignment of the overhang defenders and linebackers create more uncertainty for a quarterback and offensive line when it comes to blitz packages. Any one (or more) of the overhang safeties or linebackers could blitz, or twist, which makes it difficult to manage pass protection - because they all come from the same look.

Lastly, the five defensive backs provide for a great deal of flexibility in coverage scheme. Pretty much any coverage scheme can be run out of this pre-snap formation. Cover-1, where the free safety plays a center-field zone and the two cornerbacks play man coverage, or Cover-3, where the two cornerbacks drop or bail to cover deep thirds of the field and the free safety covering the middle third. One of the overhang safeties could also drop back, enabling either a Cover-2 (split safety) or Cover-4 (quarters) coverage scheme. In Cover-2 man, the safeties play zone in each deep half of the field, and the cornerbacks play man coverage underneath. In Cover-4, the cornerbacks drop or bail to zone cover the two outside quarters of the field, and the safeties the two interior quarters. This latter scheme is often used in shorter field or red-zone defense. There are other options (Cover-6) that can occasionally be used, and at least a dozen variations of each scheme as well. There is also what is known as pattern-matching, which is increasing in popularity, where cornerbacks may play zone or man coverage depending on the route combination run by opposing receivers. For example, an outside cornerback may play man coverage if the outside receiver on his side runs a deep vertical route, such as a go, post, or corner route. If that receiver runs a shorter route, he plays zone coverage.

How a 4-2-5 Defense Fits with Zimmer’s Defensive Philosophy & Personnel

One of the hallmarks of Mike Zimmer’s defenses over the years has been the element of disguise. Doing multiple things off of the same formation, or showing one look pre-snap, only to change it at the snap, have been pretty consistent elements in Zimmer’s scheme. The 4-2-5 scheme would allow him to continue doing just that, and even more so as there isn’t the base-nickel package personnel distinction opposing offenses can play to their advantage. It can also provide opposing offenses fewer clues to coverage scheme or match-up advantages based on pre-snap motion.

The other aspect of a 4-2-5 that fits with Zimmer’s philosophy is that it allows a defense to play fast. In his last press conference, Zimmer said he wanted his defense to play fast and be physical (a slight change from his oft-used tough, physical, smart football team). In a 4-2-5 scheme, there are fewer adjustments needed, as there are built-in variations based on what the offensive personnel and formation is. It’s a flexible run-pass defense that allows defenders to play fast using their keys and instincts. The key to its success starts with having a stout run defense up-front, which allows for fewer defenders in the box.

Personnel-wise, the scheme fits with having 335 pound Michael Pierce and 320 pound Dalvin Tomlinson, both known as stout run defenders, or space-eaters according to Mike Zimmer, as interior defensive linemen. Danielle Hunter for that matter has also been very good against the run, in addition to his pass rush productivity.

At linebacker, Anthony Barr and Eric Kendricks are near ideal for the scheme, as they’re both fast, have range to the sideline, are both effective run fillers, with Barr an effective blitzer, and Kendricks excellent in coverage.

For the overhang safeties, Harrison Smith would fill one of those roles very well, being effective in run support, a good blitzer, and good in coverage, particularly against tight-ends. The other role might best be filled by MacKensie Alexander. Alexander can cover slot receivers, while also being a good run defender and tackler in the past (apart from last season). Jeff Gladney and Harrison Hand could also fill the other spot, as could Xavier Woods, but Woods might be best as the free safety. Gladney may be a little undersized for the role, but nevertheless has proven to be tough run defender, although he regressed in that role late in the season last year. There’s also room for rotation in that role, depending on which player seems better suited against the team at hand.

That leaves outside cornerback, and Cameron Dantzler and Patrick Peterson. Both can play zone or man coverage effectively, as needed. Peterson’s role may be a lesser and easier role than he had in Arizona, where he frequently shadowed the opponent’s best receiver, and could allow him the opportunity to improve his production. Dantzler finished the season strong last year, and if he can continue that trend, would work out well. Both Peterson and Dantzler have been good run defenders too.

How It Works Against Trends in NFL Offenses

Mike Zimmer mentioned in his press conference that one of the reasons he was making changes to his defense this year was to adapt and change to the changes opposing offenses have made in recent years. He talked about having to make adjustments weekly in game planning, and how that becomes too difficult every week over the course of a season. Presumably that means changing or adapting to a new scheme that doesn’t need new adjustments installed every week, and one better suited to defending recent trends on offense. A 4-2-5 could be that scheme. Here is how it can be employed.

Versus a Mobile Quarterback

Mobile quarterbacks have become a bit more numerous in recent years, and even the not-so-mobile can break off long runs in a broken play against man coverage. The reason for that is because in man coverage, defensive backs are focused on their man, and don’t look back to the quarterback. So, if the quarterback decides to run, they won’t know until it’s too late.

In a 4-2-5 scheme, the underneath coverage, and sometimes the deep coverage too, is often zone, including that for the two overhang safeties. That can help combat the mobile quarterback who decides to run when the pass play breaks down. Against designed quarterback runs, their overhang position outside the tackles/tight ends combined with a stout interior run defense provides an excellent alignment to defend those plays.

Versus Run-Pass Options

As mentioned above, a 4-2-5 can be effective against run-pass option plays simply because, once again with a stout interior run defense, it can handle both. A stout interior run defense with a couple big interior linemen can plug up the inside runs, along with the linebackers, while the overhang defenders can disrupt outside runs while the linebackers and defensive backs flow in run support.

Five defensive backs allow for better pass defense, including some of the short, rhythm passing attacks by having four defenders (overhang safeties, LBs) capable of defending short routes and clogging those passing lanes.

Versus Pre-Snap Motion

More teams are using pre-snap motion to either reveal the defensive coverage, or position a receiver to take advantage of a coverage mismatch, or even give the look of a pass (shotgun with an empty set for example), only to move a running back into the backfield pre-snap for a designed run, or motion a wide receiver to run a sweep.

The alignment of a 4-2-5 means the defense doesn’t necessarily have to react to all the different pre-snap motions, therein showing their hand. One of the overhang safeties can cover a slot receiver in motion just as well as the other in man coverage, without the need for them to mirror them in motion across the formation. Other motions similarly may effect individual assignments, but there isn’t a need, necessarily, to re-position in any meaningful way to the offense, to better defend against pre-snap motion by a receiver or running back.

Versus High-Low Route Combinations and Mesh Routes

Another recent trend, although it’s been around for years, is the high-low crossing route combination and mesh routes - essentially two crossing routes in opposite direction- that can be especially difficult to defend in man coverage.

Having the extra defensive back (instead of a linebacker) at all times helps defend these route combinations, depending on the coverage scheme. There tends to be more underneath zone coverage in 4-2-5 schemes, and the free safety can also play a role in defending the high crossing route, while the two linebackers and overhang safeties can take the underneath zones to break up the passing lanes.

Where a 4-2-5 Doesn’t Work So Well

There has yet to be invented a defensive scheme that works well against everything, or doesn’t require All-Pros at every position to be successful, and the same is true of the 4-2-5. Here are a couple things it can be vulnerable to.

Play-Action Passes

Because the scheme is designed to allow defenders to play fast, it can be vulnerable to deception, like play-action. With only six in the box, linebackers have to be ready to fill against the run, and so they can be prone to bite against play-action, leaving the center of the field open against a quick-hitting slant or crossing route.

Misdirection

A 4-2-5 could also be susceptible to a misdirection run or backside pass where the backside safety is taken out of the play in coverage (or block) by a receiver beforehand, allowing a reverse or screen backside against flow to work, but even still the backside defensive end would need to be accounted for, or need to over-pursue initially, for it to work.

Similarly, a deceptive run design like a counter-trey, where the right side of the offensive line blocks left, and the left side pulls to take out the backside defensive end and lead block through the hole could be a tough play for a 4-2-5 to defend, as the linebacker filling would have to take on a big tackle as a lead blocker, and the overhang safety may be somewhat out of position to make the tackle, leaving the other linebacker and free safety to make the play.

Jumbo

An offense running a jumbo package with at least one big tight-end that can block and a good lead-blocking fullback could also present some problems for a 4-2-5 on off-tackle runs, as they may be more effective at the point-of-attack. The good news here is that not a lot of teams employ a fullback anymore, so it’s less likely to encounter.

Bottom Line

We don’t know what the changes Mike Zimmer has in store for the defense this coming season, but a 4-2-5 scheme seems to fit with both his overall defensive philosophy, his recent comments about what he wants his defense to do, the player acquisitions they’ve made, and as a means of combating recent offensive trends in the NFL.