Grant Cohn: Coaches feel heat, but whose seat is the hottest?

This is a pop quiz. Put away your notes, take out a piece of paper and a pen and answer the following question:

Which are the two most volatile and gut-wrenching coaching positions on any NFL staff?

If your answer includes the head coach, you’re wrong. The head coach might have the least volatile job on the staff. He makes millions of dollars, and his failures during a game typically are small and trivial. Like that timeout he wasted in the third quarter, or the challenge flag he should have thrown but didn’t.

If your answer includes the offensive coordinator or the defensive coordinator, you’re wrong. Those are the stars of the staff, the next in line to become head coaches. If they get fired, worst-case scenario they land on other NFL teams as position coaches and work their way back up the pecking order. Coordinators have a form of job security.

Position coaches don’t. If they fail, they might have to look for a new line of work. Start selling aluminum siding door to door, or become an Uber driver.

The average fan can’t really tell when most position coaches make mistakes. If a defensive line coach or a linebackers coach fails, or their players blow an assignment on a particular play, that blunder is most likely the difference between a 2-yard run and a 5-yard run for the other team. That’s it.

But if a defensive backs coach or one of his players fails, the result could be football’s equivalent to a mushroom cloud – a 75-yard touchdown pass to a completely uncovered wide receiver. It’s a meltdown. In public. Outrage spreads throughout the stadium like a nuclear explosion. Fans would go crazy all because of the defensive backs coach and his cornerback or safety.

So, the defensive backs coach has a miserable job. One other coach lives with the same agony. Offensive line coach.

If an offensive line coach fails, if the defense bursts through the offensive line, the quarterback gets sacked for big yards, an awful look. That’s the best-case scenario. He could break his leg – Joe Theismann comes to mind. The team’s season could end then and there because the offensive line coach makes one critical error. Or even if he doesn’t make an error. The right tackle could have made the error. It’s still on the coach.

How would you like to be an offensive line coach in the coaches’ meeting the night after your players gave up six sacks? All the coaches are staring at you. The room is silent, tense. You wouldn’t want to look at the head coach. You wouldn’t want to read the papers. You’d want to hide under the table. When you got there you’d find the defensive backs coach. Their egos and their jobs are always on the line.

Because you’d be the scapegoat. You’d be the guy holding back the whole team. An offense can’t function with a terrible offensive line, just like a defense can’t work with a dreadful secondary. Those are the units that uphold order. Those players are the security guards of the team. If they fail, it’s chaos.

Fact: If a team starts going down the tubes, the head coach often blames one of those two position coaches privately. Might say something in a coaches’ meeting like, “We’d be winning if not for you and your horrendous unit.”

A good offensive line coach or secondary coach has to put all of that pressure and finger-pointing behind him and act as if the job is manageable, even though he’s privately freaking out. He has to portray poise no matter what. You try it sometime.

Extreme poise was a virtue of 49ers’ all-time great offensive-line coach, Bobb McKittrick. Lawrence Taylor might have exploded through the Niners’ offensive line unblocked, body-slammed Hall of Fame quarterback Joe Montana from behind, but McKittrick’s temperament wouldn’t change.

He’d adjust the protection, his voice calm and even. He never hurried. It’s like he was making minor tweaks to the game plan on a breezy Wednesday afternoon in Santa Clara.

McKittrick never let the fans or the players or the other coaches see him sweat. Everything was under control even when it wasn’t. Even when he was failing spectacularly. And he did fail spectacularly. It was unavoidable.

No position coaches fail more spectacularly then the offensive-line coach or the defensive backs coach. That’s why those two and only those two are the correct answers to today’s pop quiz.

Grant Cohn writes sports columns and the “Inside the 49ers” blog for The Press Democrat’s website. You can reach him at grantcohn@gmail.com.