One play from the 49ers defense that highlights why DeMeco Ryans will be a head coach

I love the play-by-play overreactions every Sunday. We should be able to look back and laugh at some of the in-game commentaries. For a couple of weeks now, some have called for defensive coordinator DeMeco Ryans’ job, wondering if he deserves the praise he’d earned from the previous year and a half.

Somebody must be blamed when something goes wrong, whether it’s on offense or defense! But when you look at the game the next day and the emotions have settled, it’s easy to see how hollow those statements are.

The 49ers have four losses this season. Two of those had nothing to do with the defense. One of them, the defense played without its starting line and a few other starters. The other came against Patrick Mahomes.

In Week 8, the Rams went three-and-out to start the game. However, they scored on their next drive thanks to a double move by Allen Robinson that gained 23 yards on 3rd & 9. Lost in that drive is that it took Los Angeles seven attempts from inside the four-yard line to score.

Two third-down conversions and another 23-yard gain on the ensuing drive led to another touchdown. This time, Sean McVay knew he’d get a specific coverage in the red area and took advantage by getting his best player matched up against a backup linebacker.

So, in 25 plays, the defense was “wrong” four times. And that was enough for some to pull the plug on Ryans. But, from a macro point of view, the 49ers were excellent all afternoon.

The Rams had nine plays against the 49ers' defense, where they had three or fewer yards to gain a first or touchdown. On one play, they gained 23 yards. On the other eight plays, they gained 12 combined yards.

In this 12-round fight, Ryans won by TKO. There’s one play that I want to highlight that illustrates how special this unit is and why Ryans won’t be in the Bay Area for much longer.

McVay and Ryans both know what the opposition is going to do. The Rams run the ball the least amount of times of any team in the NFL. When they do run it, it’s “Duo,” which has accounted for 18% of their runs, a number that leads the NFL. Read this for a detailed explanation of Duo and what everyone’s job is.

Football is a game of tendencies. If you know the opposition is set on running a specific scheme, you can manipulate their rules and use those against them. Here’s the setup:

The duo explainer above tells us that there are two overriding rules no matter what the front is. First, looking off to the left side, Samson Ebukam (No. 56) has a 1-on-1 no matter what against the offensive tackle. So, knowing this, Ryans has Ebukam, and Talanoa Hufanga (No. 29) lined up to Ebukam’s left, pinch or squeeze closer to the line of scrimmage.

Everyone knows the 49ers bring in unicorn athletes that are faster and stronger than the opposition. But there’s never enough emphasis on how well they’re coached or how often they execute, which is why we take their success for granted.

You’ll always hear, “low man wins.” When people say that, it’s about getting your helmet underneath your opponent. The player who does that generally wins. For example, in the screenshot above, look at where Ebukam’s helmet is and notice where his hands are:

The person who makes first contact with his hands inside and wins with leverage often wins the rep. In this case, Ebukam takes his defender from the play side C-gap to the A-gap, which blows the play up and forces the running back to run to the weak side of the formation.

Ebukam bull-rushed the tackle into the lap of the running back. For duo to work, the third man on the surface, in this case, the offensive tackle, has the most critical block as he’s 1-on-1. But, as you can see, that doesn’t come close to happening.

Let’s go to the other side of the line of scrimmage. The center and left guard attempt to double-team defensive tackle Kevin Givens (No. 90). Ryans knows that, so he has Givens slant and cross the center’s face, effectively eliminating the potential of a double team.

The left guard must follow the rule of stepping inside. Why? So he can prevent the weakside linebacker, who is Fred Warner (No. 54), from having a free run-through in the A-gap. The second he steps down, the guard gives himself no chance of getting to Warner.

Watch the entire play, where Nick Bosa (No. 97) does his job by crossing the left tackle’s face, giving Warner an open runway at a tackle for loss:

This play is poetry in motion. This is what it looks like when everyone does their job, and players don’t mind if they won’t show up on the stat sheet.

The Niners' defense limited the Rams to a 40 percent success rate, a below-average EPA per play allowed, and only 28 percent of their plays going for first downs. Per RBSDM, compare the output from each offense Sunday:

You want to be in the green. You want nothing to do with purple.

In a sport where your process will outweigh the results over the course of the season, the 49ers' defense still sits fourth in defensive success rate, sixth in EPA per play allowed and seventh in defensive DVOA.

They’re an elite unit because they limit mistakes, have a coach that puts them in advantageous 1-on-1 scenarios, and have players who can consistently win those battles. That’ll only improve as the defense gets healthier.

If you prefer to listen to me talk through the play and why it worked, here’s the full video: