by Derrik Klassen

After a second-place finish in defensive DVOA a year ago, the Minnesota Vikings defense has failed to maintain their strength in 2018. Each layer of the defense has experienced its own downfall, ranging from Everson Griffen's absence at defensive end to miscommunications in coverage. This is not the elite unit that was supposed to carry the Vikings to and through the playoffs.

A 27-6 blowout loss to the Buffalo Bills sticks out among the rest of their schedule, but Minnesota played poor defense for a month. The Vikings currently hold the 16th-placed defense per DVOA, including a 19th-ranked pass defense. They may look a little better to the naked eye, but that's because they've faced the weakest slate of offenses in the league. Though the past two weeks have looked more encouraging and boosted their DVOA standing, allowing 17 points to the offenses of the Arizona Cardinals and New York Jets is nothing to hang their hats on. The past two weeks are not enough evidence to suggest the Vikings' defense is "back."

Rather, the defense was allowed a reprieve before facing a juggernaut this week in the New Orleans Saints. With quarterback Drew Brees headed toward a possible MVP award, the Saints offense ranks fourth in overall offensive DVOA and fourth in passing DVOA, neither of which bode well for a Vikings defense that has struggled for much of this season.

More than a mismatch in effectiveness, though, is how the Saints' offense in particular is geared to re-expose the Vikings defense.

Starting up front, the Vikings will have their toughest task to date. Head coach Mike Zimmer traditionally constructs his defense to rush the passer with four players and cover with seven, complemented by creative blitzes on some clear passing downs. This season, the Vikings defense ranks 14th with a 29 percent pressure rate, which is plenty fine (subscription required). The dilemma is that the Saints' offensive line has allowed the least amount of pressure in the league, measuring in with just a 17.6 percent pressure rate (subscription required). Masking issues in the back end through pressure up front is not a realistic approach to take for this game. With that in mind, there is an abundance of reasons to worry about how the Vikings' pass defense will hold up.

One of the primary mismatches for this game is how effectively the Saints play through running back Alvin Kamara as a pass-catcher. Not only is Kamara a threat to catch checkdown passes and work in space, but he can line up as a legitimate wideout and force defenses to adjust to him. Kamara's 362 receiving yards are the third-most among all running backs and the second-most among Saints' pass-catchers, trailing only wide receiver Michael Thomas.

Once revered for their ability in coverage, linebackers Anthony Barr and Eric Kendricks have not been reliable this season. In turn, the Vikings have been the worst team versus running backs in the passing game this season, per DVOA. A few weeks ago on Thursday Night Football, Todd Gurley and the Rams laid down the blueprint on how exploitable Minnesota's linebackers are versus running backs.

(Click here if you are having trouble loading the image.)

In this coverage design, the strong side (right) of the formation is overloaded by the defense. The Vikings play four-over-three to the trips set with a single high safety shaded toward that side of the field. The other two pass-catching threats -- a lone wide receiver to the left and Gurley in the backfield -- are left one-on-one. Barr, responsible for Gurley on this play, may have been more consistently capable of running with Gurley in previous seasons, but the Rams' superstar got the best of him here. Gurley simply widened to the seam and burst up the field toward the back of the end zone, leaving a hesitant Barr in the dust. As athletic and skilled as Kamara is, he should be able to replicate Gurley's success.

The Vikings' defense also struggles with leaving running backs and tight ends alone underneath. An occasional botched pickup of a late-releasing running back or shallow crosser is bound to happen to any defense, but it is all too common for the Vikings.

(Click here if you are having trouble loading the image.)

(Click here if you are having trouble loading the image.)

In both of these examples, a linebacker trails off into the intermediate area of the field without the proper awareness to find underneath receivers to match. The first play is the fault of Barr for not accounting for the running back leaking out of the backfield, while Kendricks can be faulted in the second play for not catching the tight end crossing underneath. Regardless of who is the culprit on a given play, miscommunications such as these lend to the Vikings being the team most susceptible to giving up first downs on first and second down, when teams are most likely to target short routes such as these. Having this problem severely waters down their prowess on third down -- one of the few areas in which the Vikings defense still performs well.

A final point of contention in this game is the Vikings' execution in two-high coverage shells and how that often leads to big plays that should not happen. True to Zimmer's m.o., the Vikings run a fair amount of Cover-2, Cover-4, and other two-high shells, but the execution has been unpredictable from play to play and from game to game. More specifically, safeties Harrison Smith and Andrew Sendejo have often struggled to read and react to deep crossers or intermediate in-breaking routes the way you might expect from a talented duo.

(Click here if you are having trouble loading the image.)

Smith, the safety over the left hash to start the play, gets put on spin cycle here. The Cardinals motion Larry Fitzgerald (left), then ask him to cut across the field at about a 10-yard depth. Smith initially creeps down to follow Fitzgerald, but slot receiver Christian Kirk (right) cuts across opposite of Fitzgerald at a deeper depth. By the time Smith realizes Kirk is moving the other way, he has already given up the deep area between the numbers and the sideline. Given the cornerback initially trailed Fitzgerald, he is still relatively shallow when Kirk is making his way to the deep sideline, allowing Kirk more than enough room to catch a pass from Josh Rosen.

Mistakes of this nature, as well as other coverage busts such as Barr being forced to cover Cooper Kupp and conceding a deep touchdown, are why the Vikings are one of the worst teams in preventing explosive passing plays. According to Bill Connelly of SB Nation, the Vikings are the 31st-ranked defense in passing marginal explosiveness, which is a measure of how often a team is giving up explosive plays relative to their down-and-distance and field position. Compare that to the Saints' offense, which ranks 13th in passing marginal explosiveness and has the fourth-most passing plays of 25 or more yards, tied with the Packers, Rams, and Chargers.

In every way, the Saints' offense is crafted to give the Vikings' defense fits. Considering the Vikings' defense has struggled versus lesser competition, facing a Saints offense that harps on their biggest issues -- pass-catching running backs and explosive plays in the passing game -- is the perfect storm to set the Vikings back after two solid performances versus the Cardinals and Jets.

It may be the case that Zimmer irons out the defense's kinks down the line. With as much talent is on the roster, there is reason to believe things can be turned around as the team fights through the playoff race. Unfortunately for the Vikings, this is likely not the week when the turnaround starts. For now, their defense is a movable object that does not appear prepared to contend with the unstoppable force that is the Saints' offense.