49ers film room: run defense in week 13 highlights season-long struggles
Missed tackles, blown assignments, and a lack of talent and depth allowed Bills to score 35 points in a blizzard.
The 49ers defense came out of week 13 giving up 35+ points again for the second straight week and mostly at the hands of the opposing teams’ running games. The defense has been without its star player, Nick Bosa, is still missing other pro bowlers/all pro players, and it’s only other star, Fred Warner, playing on a fractured ankle.
The result: a 35-10 loss in a snowy game in Buffalo.
Granted, some of this can be mitigated by the offense scoring points and sustaining drives (which they clearly couldn’t do), but the systemic issues in these two games aren’t a matter of simply just being on the field longer and being tired or fatigued, though that plays a part. An examination of the causes of multiple explosive runs given up are mainly due to player execution and mental errors in simple assignments.
Combined with a lack of defensive depth behind the regular starters plus rookies playing 2000+ snaps, what you see on TV is the end result. This season across the offense and defense, per Pro Football Focus’s Jeff Deeney, 49ers rookies have already played 2200+ snaps through 13 weeks. They played 793 all of last season.
In two nationally televised games the last two weeks, the issues became front and center for the entire football world to see. The once proud franchise standing tall behind a stout defense was being gashed on run after run after run. In the Bills game, it really wasn't a matter of bad scheme or coaching. Players just simply aren’t executing things like basic tackling or are triggering too slow even if they are in position or are playing themselves right out of position.
On the Bills second drive, their first ending in a touchdown, the defense was in prime position to give the Bills a fight in the low red zone in the snow where they could have slowed the game down but they lost contain on a first down run on the perimeter and the Bills answered with the game’s first touchdown.
The Bills preferred run play this game was “duo,” a run concept that creates new gaps with double team blocks up front on the defensive tackles instead of using pullers or lead blockers. It’s commonly referred to as “power without the puller.” They’re running it with a bit of a twist though too. They brought in an extra offensive lineman and moved receiver Mac Hollins into the formation.
This gives them essentially three potential double teams in the front but with the 49ers crowding the line of scrimmage (they’re also in man coverage), the Bills are able to seal the defense inside and bounce the run as James Cook reads the gaps inside out. The defenders on the edge, Ji’Ayir Brown and Charvarius Ward, are now responsible for the edge.
Brown did his job by squeezing and getting his head in the D gap. Ward becomes the unblocked force defender on the edge and must trigger and make the play. This is just classic “make corners tackle” that has become synonymous with strong run games. He has to replace on the edge if the running back comes to him. He did, but he triggered too slow and Cook beat him the pylon.
While Brown may have been gap sound on the above touchdown, he was less gap sound later on in the 2nd quarter where he was the primary gap defender on two explosive running plays, one that went for a 65-yard touchdown.
On Cook’s 65-yard touchdown run, the 49ers end up in quarters coverage behind the front to match the same six offensive line formation with Mac Hollins in the wing again. In quarters, the run fits for the safety are the alley to the open side away from the tight end, fitting outside the defensive end between the slot and end.
If there’s a closed side tight end and a receiver in a wing, the safety like in the above play, Brown has to take the gap inside the corner with the corner, Ward again, as the edge defender. That puts Brown inside of the new gap where Hollins ends up.
This is the same play as the earlier touchdown. Brown gets downhill to fill the D-gap, but can’t make the tackle. What should only be a 3-yard gain turns into a 65-yard touchdown. Later on the next drive, it ends up being Ward who’s caught out of position when I originally thought it was Brown. Either way, it was the same exact concept as the two above.
With Hollins in tight to the formation again, Ward is his defender in coverage. The nickel, Nick McCloud, is the edge defender in man coverage on Kalil Shakir (No. 10). Brown is covering what would theoretically be the tight end, but it’s a sixth offensive lineman again.
Ward gets caught up in the wash and doesn’t get outside when Hollins releases outside the sixth lineman. Brown ends up playing the correct gap even though the Bills push the gaps to the perimeter but Ward is unable to get off the block of the lineman.
This is just essentially a pick route against man coverage for the run game with a lineman and receiver. It worked. Brown gets his head inside his gap again, but Ward is not there outside of him to fill and the Bills tack on another explosive run.
Here, on yet another duo run call, Brown got his head into the correct gap but couldn’t get off the block and as a result the Bills earned another explosive run up the middle.
Missed tackles have also been an issue, with the defense sitting at 112 through 12 games. There were 19 missed tackles in week 12 at Green Bay and only six versus Buffalo.
Here, Dee Winters fills his gap but misses the tackle and as a result, Cook turns a no-gain run into an explosive run of 11 yards. Missed tackles aren’t inherently bad, it’s when they occur and what happens as a result.
Rookie Malik Mustapha also had a poor game here in run defense as well, where he misplayed cutbacks and missed tackles, all leading to explosive runs for the Bills offense.
Here, he fills the correct gap, the A-gap, lunges for the tackle, and misses completely while trying to wrap up at the legs of Cook. This is just a fundamental tackling mistake and Cook ran right through the attempt.
On two separate cutbacks, he blocked completely out of his gap after filling as the backside leverage player in the run fit. As the backside leverage defender, his job is to tempo the running back and plug any gap on the backside to prevent cutbacks from happening.
On both run plays, Mustapha goes to fill his gap, overruns both plays, and gets blocked and prevented from playing the cutback. Mustapha has been playing pretty well otherwise but the rookie was bound to make a few mistakes along the way and they just happened to pile up in this game.
It was critical he maintain leverage outside-in in a single high defense and work to funnel the ball carrier back into the primary support but he was unable to and the Bills were allowed to take advantage.
Outlook
Nick Sorensen has come under fire nearly all season any time the defense struggles. The truth is, the lack of talent and depth caught up with the 49ers weeks ago and is compounded with the absence of Nick Bosa, Dre Greenlaw, and Talanoa Hufanga. The defense was also at one point missing Charvarius Ward for tragic reasons, and Fred Warner has been playing with a broken or fractured ankle since week 4.
Yes, every team is injured, beat up, missing players, but I don’t think many teams are missing the caliber of players that the 49ers are on defense and I don’t think any team has faced the kind of off the field adversity this team has this season either.
The depth brought in this past offseason to play alongside the stars has been subpar. Leonard Floyd is lukewarm, Yetur Gross-Matos is non-existent despite playing meaningful snaps, and the rookies are getting their baptism by fire and learning hard NFL lessons. Sorensen is less of a problem than the roster and defense he was handed.
The front office, Kyle Shanahan, and John Lynch, left him out to dry way before the season ever started, in fact, before the dust had even settled on last season. In addition to that, 33 defensive players have taken a snap on defense this year.
The unfortunate thing in all of this is that Sorensen will unlikely be back as the defensive coordinator next season. I think that would be a mistake in a league where we are seeing how continuity and consistency of coaching breeds the most success.