INDIANAPOLIS -- The hardest part of finding a quarterback for Mike Zimmer?

Not wanting to regret his decision.

Less than two weeks ahead of free agency, with nothing but speculation on what the Minnesota Vikings might do at quarterback in 2018 and beyond, Zimmer noted the challenges of going through the process to find the right fit.

Vikings coach Mike Zimmer said that if he picks the wrong quarterback, he could be in trouble. Hannah Foslien/Getty Images

On March 14, Case Keenum, Teddy Bridgewater and Sam Bradford are slated to become free agents. All three are "definitely" options to consider, according to Zimmer. Finding a quarterback in free agency or through the draft are also possibilities.

But picking the wrong one? That's Zimmer's trepidation.

"If you go with the right one and he does like you anticipate, then everything is good," Zimmer said Thursday. "If you pick the wrong one, it's hard to win in this league without a quarterback. If you pick the wrong one, this whole thing can go downhill."

The Vikings coach later followed up in his second media session at the NFL scouting combine with exactly what's at stake if Minnesota doesn't nail this crucial decision.

"It's important for myself and [general manager] Rick [Spielman] and the organization to pick the right guy that is going to help us continue to move forward," Zimmer said, before quipping: "If we don't do that, then I'll probably be fired."

Zimmer noted money as one of the primary areas of concern in the Vikings' process of determining whom they will sign. The decision could cost the Vikings upward of $28 million to $30 million per year if they enter the Kirk Cousins sweepstakes in free agency. That figure might be lower if the Vikings stick with one of their current quarterbacks, but Zimmer does not want to sacrifice their strength, a defense that ranked No. 1 in the league in the regular season and allowed them to win close games. Overpaying for a quarterback could lead to an inability to grant contract extensions and bring in pieces to bolster the unit.

"If you pick the wrong one, this whole thing can go downhill." Vikings coach Mike Zimmer

Zimmer said the reason the team has won 39 games since 2014 is "not because we've had this one guy or that one guy. Let's make sure we keep understanding the team is why we have done good things.

"You just have to pick out the right [quarterback] that's going to help your football team the best. And where you can still do things at other positions. You don't want to go crazy here."

Zimmer praised all three Vikings quarterbacks for their contributions but pointed out the uncertainty with each option. Keenum posted a career-high passer rating (98.4) and led Minnesota to the NFC Championship Game in 2017. The small sample size Minnesota has to work with in determining whether Keenum can replicate his success from last season remains the biggest question.

"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, his record wasn't great; is it because he didn't have a good team around him? Did he play with a good defense? All those things enter into it. All those factor into it. At the end of the day, it's a guess and a hunch."

With Bradford, Zimmer said nothing medically concerns him about the quarterback's knee but called his injury issues "degenerative." The 30-year-old quarterback, whom Minnesota had on the books for $18 million in 2017, played in six quarters last season. He suffered a noncontact injury to his left knee during an electric performance in Week 1.

Zimmer said tight end Kyle Rudolph and Bradford went skiing last week. Rudolph told KFAN that he underwent surgery recently on his right ankle, which he injured during a game at Carolina.

Whether Bradford can stay healthy is Zimmer's chief concern.

"It's his history of being hurt," Zimmer said. "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."

One season removed from the gruesome knee injury he sustained at the end of the preseason, Bridgewater's sample size also poses challenges for the Vikings. The two passes he threw in the fourth quarter of a blowout win over the Cincinnati Bengals marked the only game action he saw in 2017. One day after the Vikings' loss at Philadelphia in January, Bridgewater said he "definitely" wants to be a starter next season. Whether he can return to his 2014-15 form remains in question.

"I'd love to see him more," Zimmer said. "In practice, he did some really good things. Sometimes scout-team quarterbacks and the scout-team corner are kind of the same way; there's no fear if they throw an interception or get beat on a pass. It's not a big deal because the crowd's not going to jeer them, they're not going to get written up by you guys saying they suck. You can make mistakes in practice by just doing whatever you want to do and not having that affect you. So it's really hard to evaluate just in practice.

"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. 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."