Off-season Primer: NFC North

Any way you slice it, the NFC North looks like one of the toughest divisions in football. What will the two teams on top do to stay there, and how can the two upstarts turn their fortunes around?

Any way you slice it, the NFC North looks like one of the toughest divisions in football. The Green Bay Packers, who won the division in 2014, came within a few highly improbable plays (and a few more odd play-calls) of the Super Bowl. The division's wild-card entrant, the Detroit Lions, rode a vastly improved defense to their best record since 1991. The Minnesota Vikings and Chicago Bears, who brought up the rear last year, are undergoing earnest improvement campaigns led by coaches who believe in fundamentals and building a team the right way. The Vikings are improving on offense with quarterback Teddy Bridgewater at the helm, and the Bears accomplished one of the more remarkable assistant coaching upgrades in NFL history when they replaced defensive coordinator Mel Tucker with former 49ers mastermind Vic Fangio.

• MORE OFF-SEASON PRIMERS: AFC North | NFC South | AFC South

It's not impossible to see any of these teams making the playoffs in 2015, but they'll have to get through each other in the regular season to do so. What will the two teams on top do to stay there, and how can the two upstarts turn their fortunes around?

• Let the off-season begin: Notable 2015 NFL free agents by position

Chicago Bears

• Key free agents: QB David Fales, QB Jimmy Clausen, FB Montell Owens, WR Josh Bellamy, WR Josh Morgan, TE Zach Miller, TE Dante Rosario, G/C Brian De La Puente, OL Eben Britton, DT Stephen Paea, DE Austen Lane, DE Trevor Scott, LB Darryl Sharpton, MLB D.J. Williams, LB Lance Briggs, MLB DeDe Lattimore, CB Charles Tillman, CB Demontre Hurst, CB Al Louis-Jean, CB Sherrick McManis, S Chris Conte, S Anthony Walters, S Danny McCray, LS Jeremy Cain, K Jay Feely

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• Free agents of note: Obviously, there will be a lot of changes on defense for this team -- and after the Mel Tucker disaster, that's a good thing. Fangio can run a 4-3 or 3-4 base, so that's not a problem, but he'll surely need a big, aggressive defensive tackle in the middle, and that's where Paea could come in. Only Detroit's Ndamukong Suh and Buffalo's Kyle Williams had more total pressures at the position than Paea's 47, and he's also become an above-average run defender. Briggs and Williams have been slowed by injuries, and the Bears may decide to move on, though John Fox has some history with Williams from their days together in Denver. The smart move here would be to let Fangio lead the charge (and change) at linebacker, as he has very specific designations for his defenders at that level. Tillman, one of the greatest players in franchise history, missed most of last season with a torn triceps and would be back in a minimized role, if at all.

• Positions in need of improvement: Well, pretty much everywhere on defense. The line is too old, the linebackers are iffy, and the secondary (especially the safeties) was hide-your-eyes awful in 2014 when cornerback Kyle Fuller wasn't on the field and healthy. This will be the Bears' primary challenge on the way back to respectability, though we'll see pretty soon how much of their failings were a matter of scheme and coaching. Fangio's brilliance can hide a lot of flaws. The Bears are stuck with $29 million in cap charges for Jay Cutler and Jared Allen alone in 2015, so depending on how much they want to spend in free agency, Brandon Marshall could be the odd man out -- he'd save the team almost $8 million as a post-June 1 cut. The offensive line is better than it's been in recent years, given that the Bears had to trot out nine different combinations due to injury, but Jermon Bushrod's work at left tackle could (and should) be under some scrutiny.

Detroit Lions

• Key free agents: QB Dan Orlovsky, FB Jed Collins, TE Kellen Davis, C Dominic Raiola, OT Corey Hilliard, OL Garrett Reynolds, OG Rob Sims, DE George Johnson, DE Darryl Tapp, DT Ndamukong Suh, DT Nick Fairley, DT C.J. Mosley, DT Andre Fluellen, LB Ashlee Palmer, CB Rashean Mathis, CB Josh Thomas, CB Cassius Vaughn, S Isa Abdul-Quddus, LS Don Muhlbach, K Matt Prater

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• Free agents of note: The obvious names here are Suh and Fairley, who have been the heart of Detroit's amazing defensive line. Suh is on a Hall of Fame track and will likely get a contract from some team in the J.J. Watt stratosphere (six years, $100 million, $51.8 million in guarantees). Team president Tom Lewand has expressed optimism in Suh's return, but that's going to be a tough deal to swing without gutting the team in a depth sense. In 2015 alone, the Lions have over $38 million tied up in just two players -- quarterback Matthew Stafford and receiver Calvin Johnson -- and unless Suh takes a heavily back-loaded deal with a creative signing bonus, there wouldn't be enough left to take care of other potential free agents, or much of anything else. Fairley has been hampered by injuries on the field and behavior concerns off it, and the way Mosely played in 2014 might give Lewand and his staff a cheaper option at that position. Mathis had a great season in 2014 and would be worth bringing back as a mentor to a young secondary.

• Positions in need of improvement: The Lions have intriguing talent at running back with Joique Bell, Reggie Bush and Theo Riddick, but unless they're expecting one of those three to break out, the team should look to the draft to enhance the ground game. First-round tight end Eric Ebron underperformed miserably, and the offensive line will need a little help, especially at left guard and right tackle. Depending on the Suh situation, defensive tackle will also be a need, and getting help at nickel corner would also be a good plan.

Green Bay Packers

• Key free agents: QB Scott Tolzien, QB Matt Flynn, FB John Kuhn, WR Randall Cobb, T Bryan Bulaga, DT Letroy Guion, DT B.J. Raji, LB Jamari Lattimore, CB Davon House, CB Tramon Williams, CB Jarrett Bush

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• Free agents of note: Cobb has proven to be one of the most remarkable multi-position receivers in the game, and he'll get a big payday from someone. Cobb has expressed a preference to stay in Green Bay -- and why not? -- but if bigger money comes calling, the Packers will need to replace his production. Bulaga had an excellent season in 2014 after dealing with years of injuries, and the Pack may want to bring him back to solidify what Aaron Rodgers called the best line he's played behind. Williams has been up and down over the last couple of seasons, and given general manager Ted Thompson's merciless attitude toward veterans with uncertain futures, Williams probably has his bags packed. Raji missed the whole season, but his play had grown inconsistent before he tore his bicep.

• Positions in need of improvement: The Packers have had one of the NFL's more creative secondaries over the last few years, and they could be getting more creative in the near future with Williams, House and Bush all on the open market. A true replacement for Raji, a real hole-plugger at defensive tackle, seems to be a necessity. The linebacker position could also be an issue to address -- Julius Peppers has a $12 million cap hit in 2015, and much of that could be saved with his release.

Minnesota Vikings

• Key free agents: QB Christian Ponder, G Vladimir Ducasse, G Joe Berger, DE Corey Wootton, DT Tom Johnson, MLB Jasper Brinkley, LS Cullen Loeffler

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• Free agents of note: Nobody, really. Wootton and Brinkley have value as situational players, but outside of that, there's nobody in desperate need of re-signing. Obviously, the Adrian Peterson situation bears watching -- Peterson is still suspended by the league due to domestic abuse charges, and the team would save $13 million in cap space if they released him upon his reinstatement.

• Positions in need of improvement: The receiver position is the major focus this off-season, or at least it should be. Second-year receiver Cordarrelle Patterson found himself on the bench far more than he was catching passes, and offensive coordinator Norv Turner openly expressed frustration at Patterson's lack of development. One could counter that it's Turner's job to find ways for players with Patterson's rare athletic talents to contribute, but we are where we are. Veteran Greg Jennings is likely in line for a contract reality check -- he's due to count $11 million against the cap, and he'd save the team $9 million as a post-June 1 cut. Left tackle Matt Kalil was abysmal last season, and though the team probably isn't ready to give up on him, something had better change quickly. Injuries and ineffectiveness will have the Vikings looking along the offensive line for help. Minnesota has two young studs in safety Harrison Smith and cornerback Xavier Rhodes, but all other positions in the defensive backfield could be open for discussion.