The Mind of Mike must be going 100 mph right now.

Reading into Mike Shanahan’s words Monday, it almost sounded as if Rex Grossman merely had a bad day, that four interceptions weren’t completely his fault, that even the great ones have bad days.

“Heck, I’ve been with [John] Elway on some five-interception days,” Shanny said during his post-mortem in Ashburn. “It doesn’t get any worse than that. But you got to shake it off.”

Reading into the coach and architect’s words, it almost sounded as if no quarterback change will be made Wednesday, that all those demanding that John Beck get his chance to start will be disappointed — especially if the decision-maker thinks Grossman still gives the Washington Redskins a better chance to win at Carolina.

And from Shanahan’s view, not that of a clearly despondent fan base carrying pitchforks and torches, sticking with Grossman might make perfect sense.

Small picture: With the entire left side of the offensive line decimated by injury in the Eagles loss — and with your best blocking tight end out for more than a month because of a broken finger — is starting Beck, mobility and all, in consecutive road games really putting him in a position to succeed?

Big picture: If Beck fails against Carolina on Sunday and Buffalo the following week, that would be Shanahan’s third strike at choosing a quarterback in a scant 22 games — an indictment on the one position the coach professes to know more about than any other on the field.

Shanahan has done plenty to change culture in Ashburn: more accountability, continuity and, apparently, real autonomy from ownership. But Donovan McNabb’s one-and-done year and the failure to secure a capable alternative would severely undermine that progress.

If Grossman continues to start, Shanahan can keep fouling balls off and keep the two-strike count alive. Beck would remain an intriguing mystery.

(Column disclaimer: Shanahan is tough to read, so his news conference Monday could have just been an exercise in subterfuge, baiting the Panthers into preparing for Grossman while the coach readies to spring Beck on Wednesday. After all, most of America spent the preseason believing Beck would start the season opener.)

Personally, I would go with Grossman, with a caveat: He has a short leash, no more than a quarter during which he has to move the chains and get into the end zone.

If he fails, go back to Beck. If that doesn’t work, I would go with Usain Bolt, who at least can run away from the ogres trying to hurt him.

After all the galling turnovers and red-zone inefficiency Shanahan has seen from Grossman, some would assume Beck isn’t ready, that the coaching staff doesn’t believe he can start, lead and win at this point. I would counter that if Shanahan believes Beck has a real future, he wants to put him in the right spot at the right time, and this might not be it.

Anyhow, either choice — a maligned journeyman with game experience vs. another journeyman with virtually none — obviously leaves something to be desired at quarterback.

Though he has been shaping this roster for the past two seasons, Shanahan faces the frustration of so many of his predecessors in Washington.

Since Mark Rypien in 1991, Brad Johnson is the only Pro Bowl quarterback in Washington for almost 20 seasons. And the Redskins inexplicably let him go.

To find a guy to actually hold down the job behind center with aplomb for more than three years, you have to go all the way back to Joe Theismann. Yes, franchise quarterbacks don’t grow on trees. But they also don’t hide in Tibetan monasteries or live underground with prairie dogs.

With few exceptions — Chicago and Detroit come to mind — no team in the NFL has had more trouble finding and keeping the most important player on the field.

Bottom line, Shanahan isn’t alone in a search that has gone on here for almost three decades. The difference is, as the one person in the organization with the final say on personnel, his search is tethered to more than just finding the right quarterback to win next week’s game; as the architect, he needs to find the right guy for the next three to four years.

And if McNabb clearly wasn’t the guy and Grossman is currently making a strong case against himself (nine interceptions in three games), then Beck needs to be the guy, no?

If he’s not, Shanahan goes back to the NFL roulette wheel, scouring the draft or the free-agent market. Entering his third season in Washington, Shanahan would have to acknowledge he painted himself into a corner by wasting a year on McNabb and then talking himself into Kyle Shanahan’s system being good enough to prop up either Grossman or Beck.

He would have to admit he was wrong in staking his reputation on two quarterbacks that, judging by their lack of off-season suitors, much of the league has already given up on.

“We’re going to do what we think is best for our football team,” the coach said Monday, repeating what he has said about many roster inquiries.

But more than winning Sunday, Mike Shanahan also has to give himself a chance to win in two and three years, to complete the makeover. That’s not the same as “I believe in Rex and I believe in John” this season.

The coach/architect is probably at his desk now, doing mental gymnastics over that very thought.