Here is the oldest maneuver in college football, older than the forward pass and nearly as old as the booster: when the offense stops scoring, you fire the person holding the laminated play sheet.

It even works. Sometimes. It’s the football version of unplugging the router and plugging it back in. Everybody does it, it occasionally helps, and nobody can explain why when it doesn’t.

Michigan unplugged the router on Sunday.

A day after a 15-6 home loss to Michigan State, Kyle Whittingham fired offensive coordinator Jason Beck, the man he brought with him from Utah and, at a reported $3 million a year, the highest-paid coordinator in the country. Jim Harding, Michigan’s offensive line coach and assistant head coach and a longtime Whittingham assistant at Utah, will call plays for the rest of the regular season. After that comes a national search for the next Michigan football offensive coordinator.

(Every search is national. I am still waiting for a program to announce a modest regional search, limited to candidates within a reasonable drive.)

Whittingham’s statement had the soft, carefully sanded quality these statements always have: “The results have not matched our desired outcome, and I felt that a change in leadership was required for our offense.”

That’s a polite way of describing numbers that are not polite. Michigan is 5-4 and ranks 132nd of 138 FBS teams in total offense. Against the Spartans it gained 192 yards, turned the ball over four times, gave up five sacks and converted 2 of 10 third downs. It has now gone scoreless in the first half at Michigan Stadium three times this season, which, according to ClickOnDetroit, hadn’t happened in a single season since 1934.

1934.

The Salt Lake Tribune notes the offense is on pace for the program’s lowest scoring output since 1984. Whittingham, who does not deal in decorative language, put it more efficiently after the game: “I can’t come up with one positive offensively in this game.”

So what changes now, and what changes for Bryce Underwood?

Here’s the awkward part: Underwood isn’t the starter. The former No. 1 recruit was pulled during the Oct. 17 win over Penn State, after a first half in which he went 5 of 11 for 43 yards with two interceptions. Freshman Tommy Carr, grandson of former Michigan coach Lloyd Carr, came on to lead the comeback and has started since. (Michigan football is less a program than a family reunion with a very large backyard.) Before the switch, Underwood had completed 58.1 percent of his passes this season, with five touchdowns and six interceptions.

Against Michigan State, Carr went 14 of 26 for 138 yards with two interceptions. Whittingham said afterward that the staff talked about putting Underwood in late in the third quarter, that the offensive staff recommended staying with Carr, and that he went along with it. “In hindsight, maybe we should have done that,” he said. He also said this: “Ultimately, it’s my call.”

I’d underline that last sentence, because it answers the question the firing raises.

Is the coordinator the problem, or is the problem upstream?

Let me argue the other side first, since it has a case. Beck’s offense never found a gear. Fans were calling for his job by October, and a Michigan tight end’s leaked group-chat complaints about the scheme turned an internal grumble into a public one (the player apologized). A new voice with three games left has every reason to simplify, to call what works, and to stop calling what doesn’t. An interim play-caller has nothing to protect, which can be liberating, like cleaning out a garage you don’t own.

And yet.

Michigan is averaging 3.57 yards per carry, down from 5.44 a year ago, according to the Tribune. That isn’t only a play-calling problem. It’s a blocking problem, and the new play-caller is the man who coaches the blockers. The two fumbles against Michigan State came from a running back and a receiver, not a quarterback. The quarterback decisions, by Whittingham’s own account, end on his desk. So does the decision to hire Beck in the first place, and the decision to pay him like a franchise.

Here’s my verdict, and I’ll say it plainly: firing Beck was the easy part. A new play-caller can tidy the menu. He can’t, by himself, fix an offense that can’t run the ball, can’t protect the passer and hasn’t settled on who the passer is.

What it does do is reopen the quarterback question. A new play-caller means a new set of eyes on Underwood, and an offense rebuilt around his legs looks different from one built around Carr’s efficiency. Whether Harding goes that way, or how soon, is not something anybody outside the building knows, and I’m not going to pretend I do. I say this as a person whose entire football expertise could fit on a cocktail napkin, with room left for the cocktail.

What we do know is the first test, and it isn’t a gentle one. Michigan plays at Oregon on Saturday at Autzen Stadium (3:30 p.m. ET, FS1), then finishes with UCLA and Ohio State. The interim-coordinator bounce is one of the sport’s most cherished theories, and some weeks it’s even true. If you’re tempted to back the bounce in Eugene, know that you’re backing a theory, not a fact, against an opponent that would happily disprove it.

Michigan has unplugged the router. Now it gets to find out whether the problem was ever the router, or the wiring in the walls.