Mike Zimmer has asked Norv Turner every question imaginable about quarterbacks. Has Turner played a short quarterback? Has he played a mobile quarterback? Has he played a strong-armed quarterback? Has he played a rookie quarterback?

The answer from Turner, who has been an NFL head coach or offensive coordinator for the past 23 seasons, almost always has been "Yes."

Zimmer has peppered Turner with questions about quarterbacks because as the new Minnesota Vikings coach, Zimmer has a big decision to make regarding his starter. Will he go with veteran Matt Cassel, who started six games for Minnesota in 2013 under previous coach Leslie Frazier and signed a two-year contract this offseason? Will Zimmer go with Christian Ponder, the franchise's 2011 first-round draft pick whose fifth-year option for 2015 the Vikings elected not to exercise? Or will he go with rookie Teddy Bridgewater, whom Minnesota moved up to select with the final pick in the first round of this year's draft?

New Minnesota head coach Mike Zimmer says he will take his time before naming a starting quarterback. AP Photo/Ann Heisenfelt

It is the most important decision the 58-year-old Zimmer, a career defensive coach, will make in his long-awaited first season as an NFL head coach. He must get this decision right.

My guess: Zimmer and the Vikings ultimately will turn to Bridgewater, but not without Cassel getting a shot first.

"We'll definitely consider it," Zimmer said of playing the rookie.

They should.

By all accounts, the Vikings have a healthy atmosphere in their quarterback room. Ponder undoubtedly sees the writing on the wall; it is unlikely he will be back after this season. But he needs to maintain a positive attitude so as not to frighten potential suitors next season.

Cassel has been around long enough to understand how the league works. He has been a young backup. He has been a starter. He is 32 years old and on the back end of a career that has taken him from New England to Kansas City to Minnesota. Cassel is a placeholder, not the Vikings' long-term starter.

Then there is the rookie. No quarterback was beaten up in the pre-draft process more than Bridgewater, who elected not to throw at the scouting combine and then had a shaky performance at his pro day at Louisville. Under controlled conditions -- performing in shorts with no pass-rushers in his face and throwing to familiar receivers who were uncovered -- Bridgewater misfired time and again. It scared scouts. His stock plummeted.

But the Vikings saw enough in their own exhaustive workout of Bridgewater to trade with Seattle in order to select Bridgewater No. 32 overall. Instead of being put off by the pro day, Zimmer and Turner relied on their evaluation of Bridgewater's college career. In three seasons as Louisville's starter, Bridgewater completed 68.4 percent of his passes, and as a junior he threw for 31 touchdowns with just four interceptions.

"We're really, really happy we got him," Zimmer said. "He has been very competitive, very coachable, very smart, hardworking. All the things you really want from your quarterback, he's been. He's not tried to come in there and be someone he's not. So we're happy with him. He works very, very hard. He studies hard. He's thrown the ball. He's got a good, quick release. So we tend to go over what happened during the course of his career more so than one pro day."

Zimmer said he and Turner won't decide on a starter until they've seen all three candidates in training camp and, likely, preseason games. Zimmer said a lot will depend on the rest of the team, particularly the offensive line. The worst thing the Vikings could do is put Bridgewater in as the starter without adequate help around him.

Regardless of which quarterback is chosen, Adrian Peterson will be his "best friend," Zimmer said. The Vikings want to open up space for Peterson so defenses cannot overload the box in an attempt to bottle him up. Part of being able to do that will come from throwing the ball downfield.

If Bridgewater is going to earn the starting job, he will have to prove he can do that. One quarterback evaluator likens Bridgewater to a cross between Cincinnati's Andy Dalton and Kansas City's Alex Smith. That is not the highest praise, and if Minnesota is going to compete for division titles in the talented NFC North, the Vikings will need Bridgewater to be better than that.

The good news is Turner has a proven track record of developing quarterbacks. He has only started a rookie quarterback in 12 games during his career, however, and all of them came in 1994, Turner's first year as Washington's head coach. The franchise drafted two quarterbacks that year: Heath Shuler third overall and Gus Frerotte in the seventh round. Shuler started eight games; Frerotte started four.

Given an early Vikings schedule that includes road games at St. Louis, New Orleans and Green Bay and home games against New England and Atlanta, I'd be surprised if Zimmer went with Bridgewater to start the season. But if Cassel struggles against those teams, the Vikings certainly could pivot to Bridgewater during the season.

Zimmer has a lot of questions to answer as he embarks on his first season as a head coach, and none will be bigger than this one: When will he be willing to turn to the Vikings' quarterback of the future?