The NFL is famous for change at the top of the standings. History shows that as many as half of a previous season's playoff teams will miss the postseason the following year due to a combination of injury, regression and roster turnover. While some of 2015's playoff teams are on firmer ground than others, all 12 face issues that may cost them a postseason berth in 2016. Here are the biggest fears for each of last year's playoff teams.
Denver Broncos: An injury to the defense
The obvious answer for Denver is quarterback play, but we expect the Broncos to struggle in the passing game after Peyton Manning's retirement. They're prepared for that contingency; besides, Denver's air attack was pretty poor last year. What would really doom the Broncos is a major injury to the front seven -- say, to Super Bowl MVP Von Miller. Trevor Siemian seems like he'll be a capable game manager. If the Denver defense can't keep up, the Broncos are in trouble.
Carolina Panthers: The secondary continues to falter
Letting Josh Norman walk to Washington might have been a great idea from a salary cap perspective. The former Panthers CB certainly looked washed in Week 1. Yet Carolina's secondary is a work in progress (and that's being extraordinarily generous). The growing pains are indicative of a larger trend for the Panthers. Outside of a few notable stars, Carolina has tried to make the most out of less-than-elite talent in the draft. Counting on unproven rookies and second-year players in the secondary could backfire.
New England Patriots: Tom Brady starts to show his age
We're all expecting Brady to come back and be the ol' Touchdown Tom starting in Week 5. What if the fact that he's 39 years old catches up to the future Hall of Famer, though, especially after sitting out four weeks for his DeflateGate suspension?
Arizona Cardinals: Patrick Peterson can't carry the defense by himself
When healthy, Arizona's secondary is one of the better units in the NFL. Unfortunately for the Cardinals, there are injury questions across the board, other than Patrick Peterson. As the Patriots demonstrated in Week 1, teams will completely avoid testing Arizona's No. 1 cornerback. After all, why throw it anywhere near Peterson when Arizona is so bad at defending the pass everywhere else?
Matt Kartozian-USA TODAY SportsMatt Kartozian
Cincinnati Bengals: Marvin Lewis exists
We won't mince words here. Lewis is coaching for his job this year. The Bengals have elite talent on both sides of the ball, including one of the best QB-WR combos in the game with Andy Dalton and A.J. Green. The only thing that can stop Cincinnati from a return trip to the postseason is the coaching.
Minnesota Vikings: The defense is overrated
I'm not saying that the defense is in fact overrated. The point is that if the Vikings vaunted unit ends up faltering a bit this year, Teddy Bridgewater's absence and questions about the offensive line could sink Minnesota's season. While the Vikings were impressive against Marcus Mariota and the Titans in Week 1, the front seven seemed to wear down a bit toward the end of the game. It's something to keep an eye on.
Brad Rempel/USA TODAY Sports
Houston Texans: Brock Osweiler proves to be a career backup
We're rooting hard for Brock Osweiler to succeed in Houston, and he looked solid in Week 1 after knocking off some rust early. A win over last year's Wild Card round tormenter would go a long way toward calming any fears about his ability to lead the Texans' offense. Moreover, Houston needs Osweiler to control the pace of the game and keep the defense off the field early in the season, allowing J.J. Watt to rest and get fully healthy after an offseason of injuries. Watt seems fine, but a little bit of R&R during the games couldn't hurt.
Troy Taormina-USA TODAY SportsTroy Taormina
Washington Redskins: 2015 ends up being a fluke
Washington's Week 1 game plan on both sides of the ball wasn't great (just ask the Giants), but natural regression is a bigger concern in our nation's capital than coaching. Both Kirk Cousins and Bashaud Breeland look poised to take steps back this season, which may ultimately doom Washington. And even if Washington's Week 1 woes weren't his fault, Josh Norman might not be the answer, either.
Kansas City Chiefs: A lack of a big-play threat
Kansas City has some capable backups but Jamaal Charles isn't getting any younger, and Alex Smith doesn't have the arm to keep defenses honest downfield. Having Jeremy Maclin is nice when defenses key in on Smith's affinity for checkdowns and finding his tight ends, but Smith isn't the ideal QB for the speedy wideout.
USA TODAY SportsJohn Rieger
Green Bay Packers: The linebacking corps isn't that great
We're big fans of rookie LB Blake Martinez, who was a much needed addition to a weak Green Bay linebacking corps. Clay Matthews has all the name recognition in the world, as evidenced by his 2015 Pro Bowl selection, but he's really not the All-Pro he used to be. The Packers will have to win offensive slugfests this season. Here's hoping everyone stays healthy on that side of the ball.
Pittsburgh Steelers: The pass rush falls apart
There's a lot of optimism surrounding Pittsburgh's young defense, and with good reason. The addition of rookie nose tackle Javon Hargrave should reinforce a Steelers defense that was third in sacks (48) in 2016. The question is whether the Steelers can ge get enough pressure from its edge rushers to mask an average secondary that finally has some young talent developing on the roster.
Getty ImagesJustin K. Aller
Seattle Seahawks: The offensive line is miserable
We've been saying it since the preseason. We said it when Russell Wilson went down with a (minor) ankle injury in Week 1. And we will continue to say it until we're blue in the face: Seattle's offensive line is atrocious. The Seahawks probably have enough talent on the rest of the roster to overcome that deficiency and make the postseason, but don't count on a deep playoff run unless Seattle can somehow figure out its blocking woes.