Why the 49ers’ pass defense has fallen apart — and can it be fixed?

Over the last four weeks of the 2019 season, the 49ers’ formerly dominant defense has taken multiple hits. Can this be solved?

“Obviously you want to be tighter in coverage, but if a team is running quick game you want to be able to contest all of those and see if you can bat a couple at the line of scrimmage, see if you can bat a couple at the back end. And if your yards per attempt are less than, I think the number is six and a half, you’re one of the best in football. If teams want to dink and dunk at four yards, we trust that we’ll be able to knock one down, we’ll be able to get a PBU, we’ll be able to disrupt the flow of your drive to get you to a third and advantageous for us so we can get off the field. Teams don’t always want to take those check downs, but if that’s the case then we’ve just got to continue to play tighter coverage in the back end and understand up front that the ball is coming out quick to get our hands up.”

So, a combination of better pass rush and tighter coverage. Which works in theory — the 49ers are eompletely capable of playing Cover-1 or 2-Man with their personnel and locking down on enemy receivers. That’s all well and good until and unless you’re attacked with deep crossers in a man blitz, and Witherspoon can’t keep up with Cooper Kupp, resulting in an easy 22-yard touchdown.

“The crossing route? For me, I always try to look inward,” Saleh said of Witherspoon’s coverage. “That one was a hard one for him. You’re in man pressure, there’s no low hole help, it got eaten up. The way they worked, I call it a runaway route. For me, it’s a very, very hard down for a corner on that one. I always look inward. I feel like I could have helped him a little bit better. At the same time, we’ve got to play with better technique and all that stuff. It was just a simple runaway route and man pressure that had no low plug help and it didn’t get home.”

(Kelley L Cox-USA TODAY Sports)

And now, here comes Russell Wilson again — the first quarterback to beat Saleh’s defense back when it was performing at an optimal level; you could argue that Lamar Jackson was the second. Wilson completed 24 of 34 passes for 232 yards, one touchdown and one interception, adding 53 rushing yards on six attempts. Wilson faced a gauntlet, but as has been his wont throughout his NFL career, he found weak spots and adjusted. Now, the weak spots seem to be springing up everywhere, putting the pressure on Saleh to counter-punch.

“You have to be respectful to the level of the quarterback when you’re around the edge,” Saleh said of the challenges Wilson presents. “You have to be respectful to the pocket push and what could happen and being tied together and what could happen if one of your guys takes an outside move and what you need to do to counter it. But at the same time, you don’t want to handicap your guys into being so worried about where this guy’s rushing that it just becomes what I call a mush rush where no one is really getting off their blocks and getting to the quarterback.

“You’re very cognizant of your rush lanes and you still rush to go get the quarterback and understand what he likes to do, what are his tendencies, where does he like to escape, and you just play ball from there. Understand, he will break the pocket a couple of times. We’ve just got to be great in the backend. Be relentless in what we call plaster rules. Just being relentless with our plaster rules and making sure that when he breaks the pocket we find a man and stick with him. The front just has to remain relentless in their pass rush and understand that the play’s not over until the whistle blows.”

The 49ers did have success blitzing Wilson with Warner and cornerback K’Waun Williams, so there could be more of that this time around.

“Yeah, because you always feel like you’ve got to do something,” Saleh concluded. “You’ve got to be a little bit different. They’re expecting certain things and you’ve got to be able to mix in what you did, mix in some other things. There’s always a self-scout study that you’ve got to put to it, but at the same time it’s not like you can reinvent the wheel every week.”

Saleh may not be able to reinvent the wheel with the personnel he has, but new wrinkles will be the order of the day. Without them, the chances of Seattle beating his defense for the second time this season — and taking the NFC West as a result — will increase exponentially.