NFL Live breaks down which of the teams in the NFC North are in the most need to make an impact offseason move. (1:51)

MINNEAPOLIS -- In back-to-back offseasons, Minnesota Vikings coach Mike Zimmer took a long look at the deficiencies of his team and tried to figure how he could fix them.

A year ago, those efforts centered around the offense. Zimmer brought in Gary Kubiak as an adviser to work with former offensive coordinator Kevin Stefanski, and he believed the move yielded the best season of quarterback Kirk Cousins' career.

2020 NFL Free Agency • News tracker » | Top 100 free agents »

• Barnwell's grades » | Experts weigh in »

• Best remaining free agents available »

• Free-agency coverage » | More NFL »

Zimmer's recent shake-up of the defensive staff feels somewhat similar. After six years of having the same coaches in the same positions, Zimmer brought in a veteran voice in longtime Packers defensive coordinator Dom Capers to provide "fresh ideas" as a senior defensive assistant. And he promoted his son Adam, also a linebackers coach, along with defensive line coach Andre Patterson, to co-defensive coordinators.

Zimmer, who has called defensive plays since he took over the Vikings in 2014, now has two others in charge of his beloved defense and another with 25 years of experience as a head coach and coordinator (Capers) in the same room.

So how is this whole thing going to work? And most importantly, will these moves help restore a defense that declined in several key areas (19th in third downs, 15th in passing yards per game and 14th in total yards) last season?

One place to look for guidance is across positional lines.

Kubiak and Stefanski made it work last season, transitioning the Vikings' offense seamlessly. They worked together during the week to hammer out the game plan, but no one was confused on Sundays about their responsibilities. Kubiak watched over the offense from the coaches' box and Stefanski called plays on the field.

That type of working relationship is what the defensive coaches with new titles aim to achieve.

"I think it's a collaborative effort," Adam Zimmer said. "Dre and I are going to make this transition as smooth as possible. We'll work together on the game plans. I know Coach [Mike Zimmer] will be involved a lot in them. I think that the more we can collaborate and work together, the better it's going to be because we've all been through a lot of games in this league."

Mike Zimmer will have some familiar faces in new roles next season on the Vikings' defensive coaching staff. Robert Deutsch/USA TODAY Sports

Mike Zimmer saw an opportunity to create "the best of both worlds" by keeping his two defensive coordinators in charge of their respective position groups. Having defined roles was an important selling point for Patterson, who spent time with Adam Zimmer discussing which defensive areas each felt was his strength. To be able to bring their expertise and experience to the table to "become one strong fist" gives Patterson no concerns over the change.

"There will be aspects of the game plan and the other game that we both will focus on, and then come together and put it all together," Patterson said. "That's what we've been doing so far the last couple of weeks as we go through all the cutups and try to find the areas that we can improve."

Patterson's relationship with Mike Zimmer goes back more than 30 years to their days coaching at Weber State in the late 1980s. Adam Zimmer, 36, has 14 seasons of NFL experience and began working with his father seven years ago in Cincinnati. Though their first year together came with a period of adjustment, Adam quickly learned how his father wants things done.

Those pre-existing relationships should play a large role in determining how this thing works out. Zimmer made two calculated moves with his co-defensive coordinators. He promoted two coaches with whom he has longstanding relationships to help him steer the ship. Continuity is important to Zimmer, and it wasn't the right time or situation to put someone from outside his coaching circle in either of those positions.

Certain roles have changed, but the Vikings will run the same version of Zimmer's defensive scheme as they have since 2014.

The only thing that's undecided is who will be calling plays. After years of toying with the idea of passing off defensive play-calling duties, Zimmer hasn't determined whether he will call plays or turn it over to Adam or Patterson.

"We're still in the process with all that," Mike Zimmer said. "We'll figure all that out as it goes. I can always call the plays. We'll just see how it goes in the spring. We've got a plan that we'll stick to, and we'll just see how it goes. If I feel like the best thing for the team is for me to call the defenses, I will. And if I feel like it's not, then I won't. We'll just kind of work through that process as we continue to move forward."

But what is known is that the changes Zimmer made to his staff won't lessen his involvement with the defense. If anything, it gives him the confidence that his defense is in good hands, whether he's in the room or not.

"The one thing that's been really good is, these guys don't wait for me," Mike Zimmer said. "They just go out there and they get it done. They'll put together, like, a report for me. They'll have it on tape and they'll have it in written form, as well, on what they've seen if I'm not in there. I can kind of review it, and we can go back and discuss that, where I don't have to be in there every minute. That's been really good so far."

Added Capers: "I've been around a lot of different situations, and to me they're always different. They're all unique. That's one of the things that I look forward to working with Andre and with Adam, and hopefully we can form a good team.

"I know that we've got a guy who's a head coach who knows what he's doing on defense, and I've worked for offensive head coaches and defensive head coaches, and there's always a comfort level when you're working for a defensive head coach that he's going to be very involved in what you're doing."