If the 49ers lose to the 1-5 Seahawks next Sunday team management MUST fire Mike Nolan during the bye week.

There is no gray area. Nolan already is a losing coach and fans are screaming for him to get the axe. If he loses to Seattle, he will be a losing coach who lost to a horrible team, a team that’s refusing to play for a lame-duck coach, and Nolan must go.

Firing Nolan after a Seattle loss would accomplish three things.

1. It would free the organization of Nolan and of the disappointing Nolan years.

2. It would ignite a spark on the team for the second half of the season — not a big spark, a little spark.

3. It would give some other guy the chance to be interim head coach and show what he can do. If this interim is wildly successful, the team should consider him for next season — consider him as one in a pool of head-coaching hopefuls. If the interim fails, bye bye and have a nice life.

Mark Martz should not be the interim. I used to think he could do it, but his offense is too risky — too nuts, frankly — to succeed in San Francisco or maybe anywhere. J.T. O’Sullivan is lucky he hasn’t experienced extreme bodily harm under the Martz system, but that still could come.

Readers keep telling me they would like Mike Singletary to be interim in waiting. Sure. Why not? If Nolan gets fired let Singletary give it a shot. I don’t think it will amount to anything, but he might surprise people.

But, OK, what if the Niners defeat the Seahawks?

This is the tough one. I say let Nolan finish out the season. I know this notion must disappoint fans who absolutely hate him. But going 3-5 with that hard schedule is not a sin, and sure I know some of the teams the Niners lost to were not at full strength, like no Tom Brady. But come on. If the Niners win on Sunday, I’d give Nolan a chance to finish out, to show definitively what he can and cannot do. If the final record stinks, John York fires him no questions asked. And then York goes in search of somebody really good, someone who’s not a beginner, someone with an impressive body of coaching work.

— Lowell