The San Francisco 49ers run defense is bad. I know, that is a shocking revelation. I’ll give y’all time to recover.

Whether you look at basic statistics or advanced metrics or just the eye test, this team’s run defense is bad. In fact, it is on pace for historically bad numbers. Through seven weeks, the 49ers have allowed 1,296 yards on the ground. That comes uot to 185.1 yards per game. The Cleveland Browns are second worst, giving up 139.9 yards per game.

The 49ers pass defense has been inconsistent, but it has not been nearly as bad as the run defense. Of course, it is also not getting challenged at the same level as the run defense, but opposing teams really have no need to push hard through the air. The 49ers have been trailing, so they give up yards then, but even when games are close they are being gashed on the ground.

NFL Films producer Greg Cosell made an appearance on KNBR on Monday, and while he spent a lot of time talking about Colin Kaepernick, he also addressed the 49ers poor run defense. He had some interesting comments, particularly about DeForest Buckner and Arik Armstead. You can listen to the interview here, but here is a transcription of his comments on the run defense:

On what fixes are there for the poor run defense:

“I think when you don’t stop the run, it’s not magic. There’s three reasons why you don’t stop the run. You have what is commonly called gap integrity issues. That means the player’s going into the wrong gap. They’re not playing with gap discipline. No. 2, you have players who get blocked or don’t get off blocks. They either get moved, or they stay blocked too long. And thirdly, you don’t tackle well. So it’s really not nuclear physics, it’s those three things. And for the most part, those three things are happening on a weekly basis.”

On if there’s anything the 49ers can do, or stuck with what they are:

“At this point — and you’re stuck with the personnel — but as I said, As a whole, as a unit, what you have right now is you have a team that’s poor at shedding blocks, not overly strong at the point of attack, and they pay with poor pad level. Buckner and Armstead both play with poor pad level at this point. So what happens is you get moved. I know there’s a belief that some defensive coaches, and I don’t know exactly what the belief is with the 49ers coaching staff, but I know there at times is a belief that you want your defensive linemen to play, I don’t want to say play high, but to at least get their head up so they can see things. The problem, at times with that, is then you stand up too straight. And even powerfully built guys like DeForest Buckner will still get moved.

“And, the other thing that Buckner is starting to do — which in college could get away with because he was a stronger player than those he was paling against — is he’s stopping his feet on contact. Tom will tell you, in any sport, if you stop your feet, there’s not a whole lot you can do that’s positive at that point.”

It’s an intriguing point, and the video shows some of these issues. Here are a couple clips Oscar Aparicio put together from the All-22.

#49ers defensive line just gets pushed off the ball too often to succeed regularly in the run game. Buckner/Dial can't maintain position pic.twitter.com/POJJRY9WtN — Oscar (@BetterRivals) October 25, 2016

Buckner playing inconsistently against the run. Sometimes can stand his ground but others he gets moved off the ball entirely. Low man wins pic.twitter.com/M4JQwplheC — Oscar (@BetterRivals) October 25, 2016

Scheme trying to free up Bellore to make a play. Armstead sets wide, Hodges blitzes A gap; OL handles easy. Armstead turned. Bellore late. pic.twitter.com/YNcRvVwa5m — Oscar (@BetterRivals) October 25, 2016

The 49ers defensive front is getting bullied around, and you can even see it in the number of yards the 49ers are giving up before contact. Pro Football Focus tracks yards before contact, and the 49ers are getting destroyed on power and counter run concepts. I don’t think we need more stats to explain the problems, but PFF’s Ben Stockwell offered this up, putting a bow on how awful things are with this run defense.

The 49ers are allowing a league worst 7.9ypc against power or counter run concepts.



55% of those yards are being allowed before contact. — Ben Stockwell (@PFF_Ben) October 24, 2016