Kurtenbach: The 49ers returned to basics to beat the Seahawks. They need to stick with them

Kyle Shanahan didn’t see Issac Guerendo’s slide.

The 49ers’ head coach was too busy throwing his hands in the air, signaling touchdown, and pumping his fist, to turn around and see his rookie running back — tasked with running out the clock late in the 49ers’ game against the Seahawks — slide at the 5-yard line, up five points, after 76 yards of running with 1:24 to play.

It was a play worth celebrating, even if Shanahan’s touchdown signal proved a bit premature. Two plays later, San Francisco scored a touchdown to extend their margin in a nervy contest to the final score, 36-24.

Did Guerendo need to slide and delay the proceedings further?

“Hell no,” Shanahan said after the game. “We wanted him to score.”

Yes, even the big plays proved complicated for the 49ers on Thursday. That’s what happens when you play the Seahawks—weird things happen, even if the result has been the same—a Niners win—in the last six contests.

Still, there was nothing genuinely abnormal about the Niners on Thursday.

Facing a must-win game in early October, San Francisco returned to basics to beat a weary Seahawks squad.

It worked.

We’re talking about outside-zone runs, under-center play-action passes, heavy personnel, and a lot of Deebo Samuel moving around on offense.

The tried-and-true stuff.

The 49ers had been going away from that formula, even though it wasn’t broken. They were getting too cute by far more than half, particularly in the red-zone on offense and on third downs on defense.

So, whether because of the ever-increasing list of injuries or in spite of it, the Niners found themselves replaying the hits against Seattle.

They need to keep on it like an Elton John farewell tour.

The Niners rushed the ball 33 times on Thursday. No fuss, no muss, even when Jordan Mason left the game injured, they just looked at the Seattle defense and said “stop this.”

The Seahawks, in allowing 228 yards rushing, said “no.”

Per the NFL, the 49ers offense used 21 personnel — two tight ends, one running back — on 47 percent of their plays, gaining 317 yards and scoring two touchdowns. That’s the most yardage in one game the NFL has ever tracked.

That game plan — that success — wasn’t terribly dissimilar from the one the Niners deployed in their last prime-time game, the Monday Night Football season opener against the Jets. In that game, the Niners ran for 180 yards on 38 carries.

This needs to be the formula for the Niners moving forward. San Francisco needs to look like a Shanahan offense again.

That means not just running the ball with a steady diet of outside zone, stretch runs, but also using heavy personnel — two running backs, two tight ends, or both — and putting quarterback Brock Purdy under center more often so you can put the opposition in conflict by testing them with hard play-action fakes to boot throws.

Again, nothing new.

And I mean that — cut it out with the new stuff. Run the plays that earned Shanahan the “genius” label so many years ago. Get back to the ethos of his dad, Mike Shanahan.

I don’t think it’s a coincidence the two best games the Niners have played this season — Week 1 and Thursday (at least offensively with the latter) — were run-first games. The Niners have experimented this season with a Big 12-style shotgun offense. Purdy clearly likes to be able to survey the field, in full, without turning his back to it — who would like that? All it did for them was bottom out their red zone offense and leave everyone around the team stressed in mid-October.

Yes, Thursday’s game was stressful, but when the Niners needed to run out the clock with 1:39 to play but Seattle holding all three timeouts, they were able to run (almost) into the end zone on the first snap from scrimmage.

The play couldn’t have been more straightforward. The result couldn’t have been better.

That’s what the Niners’ offense was built to do.

There’s really no reason to do anything else.