How Aaron Glenn's Game Plan Won the North for the Lions

With the NFC North and the #1 Seed on the line, the Lions didn’t hope they’d come out on top against the Vikings. They went out and took what was theirs with an aggressive approach by Aaron Glenn’s defense that perfectly matched the personality of this team.

Detroit blitzed Sam Darnold on more than half of his dropbacks and played man coverage 66.7% of the time. That’s the 2nd-highest rate by any defense in a game this season according to Next Gen Stats. They also played cover-0 on 14 snaps, the most of any defense in a game this season.

The approach was designed to make Darnold uncomfortable. Glenn didn’t want him to have the time and space to sit in the pocket, read the coverage, and get the ball to his dynamic receivers like he’s been able to all season. He got Darnold playing fast, which led to him missing several throws and not attempting others that were open.

The high dose of man coverage was also meant to keep Kevin O’Connell’s well-designed route combos from dissecting their zone coverage. The Lions were physical with Minnesota’s receivers, often jamming them at the line to disrupt the timing of the passing game and force Darnold to hold onto the ball.

Just look at this example from the first drive of the game with Amik Robertson attacking Justin Jefferson at the line:

The success of the Lions’ approach played itself out in the most critical moments of the game. The Vikings finished just 3-for-13 on 3rd down and 0-for-3 on 4th down. They also took four trips into the red zone and came away with just 6 total points (no touchdowns). That’s your ball game right there.

The Vikings’ first drive was where Detroit’s aggressive tone was set, though. On the second play of the game, the Lions brought a cover-0 blitz from Minnesota’s 22-yard line:

Darnold completed this pass but took a hit on what was an uncommon and aggressive coverage for the area of the field and the situation. That had to register with him.

Several plays later, the Lions would start in a 2-high look and play man coverage. Post-snap, the two safeties would take away Justin Jefferson on the outside as well as the middle of the field - Darnold’s two favorite places to go with the ball:

Linebacker Jack Campbell would also green-dog blitz after his man stayed in to block and got another hit on Darnold:

It was clear at this point that this wouldn’t be an easy night for Darnold. The effects of the aggressive coverage and pressure were evident on the next play, a 3rd-and-9 where Darnold misfired to an open receiver:

After a sack to open their next drive, he again missed an open receiver on 3rd down despite a clean pocket:

Darnold couldn’t seem to get himself settled down all night. Just take a look at some of these throws in those critical moments in the red zone.

This was Minnesota’s first 4th-down attempt of the night. Focus on the top of the screen. I’m not sure why Darnold didn’t throw the out to Addison there:

He looked like he was about to pull the trigger. Maybe he felt pressure being driven into him and was worried he couldn’t follow through on the throw? Perhaps it was designed to be a double move and there was no option to throw the out to Addison? Who knows for sure. He still had a chance to hit Jefferson at the bottom of the screen with a better throw but again misfired high.

After a Jared Goff interception gave the Vikings another immediate red zone opportunity on their next drive, Darnold again missed more chances for six:

In fairness to Darnold, there was some pressure on both examples. Although it wouldn’t have been a factor if he got rid of the ball just a hair earlier on that first throw.

That second throw was missed because the Lions dialed up another cover-0 blitz and a free rusher was there to impact his follow-through. Darnold also had to get rid of it a bit sooner than he otherwise would have liked because of the pressure. It’s a pass that could have been hit, but it wasn’t the egregious miss it appeared to be on TV.

That said, this miss on a 4th down in the third quarter with the Vikings trailing 10-6 was bad. Darnold had the slant and the return route open at the top of the screen:

Again, I don’t know why he didn’t throw the slant on the outside at the top of his drop. I don’t know why he didn’t stick to that side and then hit the return route, which was his next read.

I can’t get into Darnold’s head and tell you what he was seeing on these plays. But he was less decisive on Sunday night than he’s been all season and didn’t play with good timing at all. Points and big plays were left on the field as a result.

But I also think the Lions defense was the driving force behind his struggles. Glenn’s scheme and early-and-often pressure led to Darnold not trusting what he was seeing.

As mentioned above, one of the keys to Detroit’s plan was the high rate of man coverage. Specifically, it was how they chose to play Justin Jefferson. Glenn felt comfortable leaving Amik Robertson singled up on Jefferson for most of the night, often times without any help. This was particularly true in the red zone.

And it worked. Robertson was outstanding.

According to the 33rd team, he shadowed Jefferson on 35 of his 43 routes, allowing just 3 receptions for 54 yards on 7 targets. You can see some of those snaps below:

Glenn did mix in some help on several snaps (primarily between the 20’s). He did a really good job of varying his looks and disguising where the help was coming from to keep the Vikings off balance. Minnesota couldn’t seem to get a feel for when Jefferson would be singled up and when he would be taken away with a double-team or the occasional zone coverage.

Below, you can see one example where the Lions dropped out into zone on the goalline after Robertson had aligned over Jefferson (Bottom of screen). That allowed them to handle this mesh concept (a man beater) and force an incompletion:

On this next example, a 3rd-and-6, the Lions would start with 2 safeties deep and appeared to be playing 2-man pre-snap. But they would end up abandoning the deep middle and bring another cover-0 blitz with a double on Jefferson:

The result was another incompletion:

On this next play, a 3rd-and-9, the Lions would again start in a 2-high shell and then bring a 5-man pressure. This time, they had a safety from one side of the field race to the other side to get over top of Jefferson and Jordan Addison:

The result here was a sack:

All of it added up to a season low in points for the Vikings and arguably Sam Darnold’s worst performance of the year (18-41, 166 yds, 0 TD, 0 INT). The Lions took home the NFC North division title, the #1 seed, and a first-round bye as a result.

They’re going to be a tough team to beat at home in the playoffs.