The Minnesota Vikings ceded 208 rushing yards en route to their sixth loss of the season. Any 200-yard rushing day is a bad day, but perhaps more frustrating is the way it manifested. While PFF only credited the Vikings with seven missed tackles, the San Francisco 49er forced more poor tackling opportunities. This led to 152 of those 208 rushing yards coming after contact with a Vikings defender.
What gives? Mike Zimmer has boasted some of the best-tackling teams in football over his time as the Vikings’ head coach. Many of those players are still in the building. Why is it suddenly so hard to bring down the ballcarrier?
Granted, the Vikings were missing a lot of players in this game. Everson Griffen, Danielle Hunter, Dalvin Tomlinson, and Michael Pierce all missed the game. Some are out for the season. Anthony Barr did not complete the contest and Nick Vigil also missed some snaps. To simply chalk it up to an injury issue would be to make unearned excuses. Like Andre Patterson said before the game, that depth is meant to play, not to be hidden. Something more is going on here.
The Vikings don’t seem to have a fundamental problem with tackling. Rather, they have a problem setting up good tackles. They aren’t leaving their feet or attacking too high or making any other mistake that a high school coach would try to iron out of his freshmen. Rather, the most subtle nuances of offense and defense are leaving the Vikings in incredibly difficult positions. From there, they have no choice but to dive at whatever piece of the ballcarrier they can get their hands on.
Without this problem, the Vikings tackled fine. They are not a fundamentally unsound team, at least not on defense. But what led the Vikings out of position requires an incredibly detailed look at the chess match between Zimmer’s defense and Kyle Shanahan’s offense. If Shanahan simply outdueled Zimmer, that’s one thing. Shanahan is one of the most highly respected offensive minds in the game. What we really have to fear is the possibility that Shanahan exposed a fatal flaw in Zimmer’s vaunted defense.
The problems a puller presents
To monstrously oversimplify things, many offensive and defensive schemes will ask players to contend with the player right in front of them. That’s the default state of affairs. The way offenses label this is “covered” or “uncovered.” If you have a defender in front of you, you’re covered. If not, you’re uncovered.
Here is one of the simpler examples. In fact, this is about as simple as Shanahan’s offense gets. It’s called a “trap” block. An uncovered lineman will crash down on a defender, freeing up a covered one. That covered one “pulls” around. This gives a defender, Armon Watts in this case, a tantalizing path into the backfield, but a blocker meets him from the side.
It’s a way to confuse defenders, if only for a moment. If your assignment was to attack between the center and guard, what changes now that the center is next to the tackle? Figuring out where you’re supposed to go will only take a moment, but in the run game, there isn’t a moment to spare.
To combat this, the Vikings employed a lot of gap exchanges. That just means that if two blockers switch places, two defenders switch assignments too. It lets the offense swirl around as much as they want, and at the end of the day, defenders don’t have to move all that much. In this case, Blake Lynch can watch the center and guard swap places, then attack the hole the running back wants to take. It’s a clean tackling opportunity, and Lynch tackles reasonably well to force a fourth down.
However, these sorts of exchanges can get confusing as the run play gets more complex. What changes when a whole new player is added to your half of the field? In this example, George Kittle pulls all the way across the formation, causing lethal hesitation from Lynch.
Hesitation from Lynch means Patrick Peterson gets blocked. With Lynch and Peterson out of the play, only Eric Kendricks has a shot to get the tackle. Kendricks has to catch up, as he starts on the other side of the play. A bad angle means Kendricks can’t tackle with leverage. And Elijah Mitchell can drag a low-leverage tackle for several more yards. Kendricks and Barr in particular were stuck in difficult leverages the entire game, thanks to hesitations and failures around them.
The problems with motion
Shanahan’s offense is designed to make your defenders think. They will motion players across the formation, swap linemen, pull blockers from one side to the other and employ all manner of tricks to stress even the most veteran players. In short, the 49ers beat the Vikings because these tricks worked. But there’s more to glean from how it all works.
There are two key problems to think about with a motioning receiver. First, someone has to cover that guy if he gets the ball. Second, and perhaps more importantly, a lot of math just changed, especially if that guy went from one side of the formation to the other. Shanahan knows how defenses will react to certain threats, and relies on that to set his players up to succeed.
All this puts Breeland, Vigil, and Smith out of position. They’re not getting a clean look at Elijah Mitchell as he weaves through them. That means they don’t get the luxury of arriving at the ballcarrier at the same time. Instead of a nice, clean opposite-hip tackle attempt, they have to dive and try to make a play, leading to some poor tackles. They aren’t necessarily “missed” tackles, and credit to the defense’s fundamentals for that, but they afford Mitchell the opportunity to fight for even more yards.
shooting the gap
One answer to the 49ers’ brand of rush attack is to get aggressive. If a blocker is going to vacate his area and pull somewhere else, there will be a giant gap where he left. If you’re quick enough, you can shoot through that gap before another blocker comes to replace him. It’s difficult to make that decision on the fly. Nick Vigil, rodeo cowboy that he is, takes these opportunities often. The risk is that if you shoot the gap and don’t get there, your original assignment will be left wide open.
Vigil is doomed before he even gets to the tackle attempt. Because Juszczyk is able to knock him off of his path, Vigil can only dive at Deebo Samuel. Samuel can easily rack up a 49-yard run, most of which is after contact. Vigil’s technique isn’t flawed, but rather, there can be no technique. He took a gamble, got knocked out of position, and had to dive in desperation.
It seems like Shanahan’s unique style of offense caused the Vikings to tackle uniquely poorly in this game. If other teams can replicate Shanahan’s brand, they may be able to replicate this result. The Detroit Lions, in particular, run a “Shanahan-lite” scheme that utilizes motions and shifts in the same way. The Lions aren’t as good at it as Shanahan’s 49ers, but challenges may still present themselves, much like they did last time. The Vikings need to get better at diving tackles — or better at preventing them in the first place.
