– The owner of a 39-25 regular-season record and two NFC North championships in his four years as Vikings coach, Mike Zimmer is nonetheless well aware of how fleeting job security can be in the NFL.

And on Thursday, with the Vikings in the midst of determining their next starting quarterback, Zimmer put the stakes of the team’s choice in stark terms.

“It’s important for myself and [General Manager] Rick [Spielman] and the organization that we pick the right guy that is going to help us to continue to move forward,” he said. “If we don’t do that, then I’ll probably get fired.”

Hard as it might be to imagine the Vikings’ upward trajectory being derailed in a year, the team’s upcoming quarterback decision might be the one with the most potential to pierce the team’s present cocoon of stability.

The Vikings, fresh off a trip to the NFC Championship Game, must decide whether any of their three in-house quarterbacks (Case Keenum, Teddy Bridgewater or Sam Bradford) can be the player to lead them to the Super Bowl. They must determine whether a free agent such as Washington’s Kirk Cousins, or possibly even a draft pick at the end of the first round, can bring them closer to a championship than any of their internal options.

And, as Zimmer cautioned several times Thursday, they must do it in a way that doesn’t hinder their ability to keep the rest of their nucleus together.

“I don’t want to talk about windows and things like that because I’m hoping it’s more than a window — I’m hoping it’s wide-open spaces,” Zimmer said. “But I do think we have a good nucleus as a team. I think it’s really, really important that we understand — and I’m not just saying this — we’ve won 40 games in the last four years. We’ve done that by being pretty good on defense. This year obviously the offense was much better, but part of the reason we’ve been winning games and staying in games is because we’ve been playing good on defense and we’ve been a smart team and all those things.

“I want to be really careful about taking away from our strength and saying, ‘OK, we’re not going to be able to do this and we’re not going to be able to do that anymore because of financial reasons or something else.’ ”

The Vikings have to make decisions on several homegrown players in the next year, when wide receiver Stefon Diggs, defensive end Danielle Hunter and linebackers Eric Kendricks and Anthony Barr are scheduled to hit free agency. It’s another factor complicating a quarterback choice already full of variables.

Zimmer said Keenum, Bridgewater and Bradford are all “definitely” under consideration to return as the starting quarterback next season, but the coach said each passer comes with questions that must be answered.

With Keenum, who threw for 3,547 yards and 22 touchdowns while leading the Vikings to the NFC Championship Game last season, it’s whether he can repeat that performance under new offensive coordinator John DeFilippo.

“We think he can,’’ Zimmer said. ‘‘It’s just kind of guessing: Is he the guy when he was at Houston or the Rams or is he the guy who played for us? Is it because he had a good team around him?”

Bradford, Zimmer said, is in good health; the quarterback was skiing with tight end Kyle Rudolph in Jackson Hole, Wyo., last week. But the long-term reliability of Bradford’s knee, after a noncontact injury limited him to six quarters in the regular season, is the “million-dollar question,” Zimmer said.

“His knee’s not great, obviously, right? It’s degenerative,” Zimmer said. “But it’s his history of being hurt. That’s the monkey wrench in the whole thing. Can you believe he’s going to play the 15 games he did two years ago, or he’s going to play the one game where he hit the turf this year? That’s the big dilemma.”

League sources told the Star Tribune earlier this week that Bridgewater’s contract will not toll into the 2018 league year, meaning the 25-year-old is headed for free agency after returning from the left knee injury he suffered in 2016.

Zimmer said Bridgewater “did some really good things in practice” after returning from the physically-unable-to-perform list in October, but he added it’s hard to use practice snaps as much of a gauge for how Bridgewater can play at this point.

“We have to go back a lot with Teddy on what he’s done in the past, him as a person, his work ethic, all those things,” Zimmer said. “Him not playing for two years and not being able to see him play in live situations, that’s concerning a little bit. But I love the guy. He’s a great kid, great competitor, a winner.”

Pick the right quarterback, and the Vikings could be among the NFC’s contenders again next year. Pick the wrong one, Zimmer said, and “this whole thing can go downhill.”

OK, then.

“At the end of the day,” Zimmer said, “it’s a guess and a hunch.”