Kurtenbach: Brandon Staley’s time with the 49ers was unremarkable. His Saints defense is anything but

The NFL is a small world — a high school reunion with shoulder pads.

Guys are shuffled around the deck of 32 teams year in, year out. And all too often, they end up staring across the field at someone they used to game plan with.

That’s what’s happening this Sunday in New Orleans. Kyle Shanahan and his San Francisco 49ers will be in town, and on the other sideline, waiting for them, will be Saints defensive coordinator Brandon Staley.

And Staley, who was an assistant with vague assignments for the Niners last season (he was certainly not the team’s shadow defensive coordinator), has a defense that’s an absolute nightmare for Shanahan’s wide-zone run game.

Yes, this game will be anything but Big Easy for San Francisco.

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Staley’s defensive scheme was, ironically, popularized by Shanahan’s predecessor in Santa Clara, Chip Kelly. It’s called the Tite Front, and it’s a real nasty look to face if you’re a team whose entire identity is based on the wide zone run.

It’s a 4-0-4 front, which means you’ve got two big defensive linemen lined up in the “4i technique” — smack dab between the offensive guards and tackles in the B gap — and an even bigger nose guard staring the center eye-to-eye. It’s a front designed to gum up the works for a team that wants to stretch the field horizontally.

And that’s exactly what the 49ers want to do. Particularly with a backup quarterback at the helm, likely down the team’s top two pass catchers from 2024.

Kelly, the offensive mad scientist, cooked this scheme up back in his Oregon days. He made it to stop his own offense. Seriously. His run-pass-option scheme became so dominant, he had to invent a defense to counter all the teams that were ripping it off. It turns out that defense is just as good at making life miserable for the wide-zone mafia that dominates the league.

The basic idea is that those defensive ends at the 4i force the offensive tackles to occupy them. The whole thing creates a traffic jam that makes it near-impossible for offensive linemen (typically the guards and center) to do their two main jobs on zone runs: double-teaming along the line and then getting to the second level to block linebackers.

While most guys on defense these days want to get into the backfield as fast as possible, Staley preaches a different kind of gospel. His linemen are supposed to fill one gap off the snap and then, depending on where the ball carrier moves, fall into another. It’s called a “gap-and-a-half” defense, and when it works, it frees up the linebackers to clean house and stop the run before it even gets started. It also lets Staley keep two safeties deep in the pass game, but because those second-level blocks rarely arrive on time (if at all), they can crash down in the run game, too.

In short, the Tite Front allows defenses to receive all the benefits of stacking the box without actually doing so.

This is the kind of defense that once made Staley a hot commodity on the coaching market. Both Sean McVay and Kyle Shanahan saw his work and decided they’d rather hire the guy than have to face him. McVay brought him to the Rams in 2020 after seeing his work with the Bears, where he helped devise a late-season defensive plan against McVay that later became the basis for the Patriots’ Super Bowl game plan. You know, the one that left the Rams with three points. As the Rams’ DC in 2020, Staley’s defense was the best in the NFL. That got him the head coaching job with the Chargers.

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After three years with the Chargers, he came back to the Niners last season as an assistant. No one can quite tell you what he actually did for the team. For whatever reason, the Niners didn’t see fit to put him in charge of the defense either before or after last season. Perhaps it was the other coaches and the way they wanted to do things — the Niners run a very different defense.

So now, Staley’s with the Saints. And he’s inherited a roster that’s better suited for his defense and a head coach and front office that’s all-in on his plan to blow up the Shanahan offense, league-wide.

The first thing Staley did as Saints DC was trade for 330-pound nose guard Davon Godchaux, an absolute beast who is a nightmare to handle at the 0 technique. Thoughts and prayers to Niners center Jake Brendel this week.

Last week, the Saints held the Cardinals to just 80 yards on outside-zone runs, and most of that came on one play where two Saints defenders ran into each other, leading to a 52-yard scamper. You take that away, and the Cardinals’ running backs averaged 2.5 yards per carry.

Compare that to the Niners’ Week 1, when San Francisco, with Brock Purdy at quarterback, averaged just three yards on 21 outside-zone carries against a five-man front from the Seahawks.

What’s going to happen when Mac Jones — who defenses don’t ever have to consider as a runner — is running this show?

“It goes back to when Kyle’s dad was calling plays back in Denver,” Staley said this week. “They’re going to run their offense… It really forces the defense to declare itself.”

Unless Shanahan has some new tricks up his sleeve and the guys up front who can execute those tricks, that declaration isn’t a problem for the Saints. Their defense — built by a former Niners head coach and brought to the NFL by a former Niners’ defensive coordinator’s protégé, as well as Shanahan’s former assistant and now top rival — was built to stop Shanahan’s basics.

It’s a small world, this NFL.

And that could very well be a big problem for the 49ers on Sunday.