Playoff field has familiar feel

The regular season ends Sunday, and the biggest remaining playoff mystery is in the AFC.

Five NFC playoff teams are set, and we know the Carolina Panthers-Atlanta Falcons winner will be the sixth team and get the No. 4 seed. Only the seedings of the other teams remain.

Five of the six AFC playoff teams are locked in, but a lot of crazy things can happen for that last wild-card spot. The San Diego Chargers are first in line and will get it if they beat the Kansas City Chiefs. But the Baltimore Ravens are right behind them and shouldn't have any trouble beating a Cleveland Browns team that lost Johnny Manziel (hamstring) and might not have Brian Hoyer (shoulder), either.

Kansas City and the Houston Texans have remote chances, but a Chiefs win over the Chargers coupled with a Ravens win would leave San Diego and Kansas City out of the playoffs. It should make for interesting drama.

Here are the trends for Week 17.

1. How the playoffs look the same: In 18 of the past 19 years, at least five new teams made the postseason after missing it the previous year. If San Diego secures a wild-card spot and Carolina beats Atlanta to win the NFC South, the number will be only four in 2014. Plus, the Pittsburgh Steelers and Arizona Cardinals were the first teams out in their conferences last year, and both are in this year. That means 10 of last year's top 14 seeds could remain in the top 14, showing how hard it is to crack the list of contenders. This is particularly true in the AFC. New England, Denver, Indianapolis and Cincinnati have all made the playoffs for at least the past three years. Pittsburgh is back in after a two-year absence. Of the teams in contention for the final spot, Baltimore is trying to return after a one-season absence, and San Diego and Kansas City made it last year. Schedules can help or hurt a contender by a game or two, but the common denominator for these teams is that they have a top quarterback. The AFC contenders have Tom Brady, Peyton Manning, Andrew Luck, Andy Dalton, Ben Roethlisberger, Joe Flacco, Philip Rivers and Alex Smith.

There are differences to a degree in the NFC, thanks in part to the drop-off in the NFC South. Carolina and New Orleans, playoff teams last year, have six wins each entering Week 17, giving Atlanta a chance to improve from 3-13 to division champion. The Dallas Cowboys knocked out the Philadelphia Eagles in the NFC East, while Jim Caldwell lifted the Detroit Lions into the playoff mix. And no coach did a better job handling adversity and injury than Bruce Arians, who deserves coach of the year honors for getting the Cardinals into the playoffs.

2. The importance of home-field advantage: The New England Patriots have clinched the No. 1 seed in the AFC, and Seattle Seahawks can lock up the NFC's top spot with a win over the St. Louis Rams at home Sunday. For the Seahawks, home field could put them over the top in their quest to return to the Super Bowl. Like Arizona, Denver and Cincinnati, Seattle had its bye in Week 4 and could use the week off that comes with a No. 1 or No. 2 seed. Halfback Marshawn Lynch hasn't shown any signs of slowing down, rushing for 1,246 yards on 266 carries, but his body needs rest. Coach Pete Carroll faces an interesting decision involving left tackle Russell Okung and center Max Unger, who are hurting. Both are Pro Bowl alternates and could help protect Russell Wilson from the Rams' potent pass rush. Okung has a better chance to play Sunday than Unger, who is coming off a high ankle sprain. It would be great to rest both Sunday, but the game is too important. The Patriots essentially have two weeks to rest banged-up players, and having home-field advantage will give them a big edge if they have to face Peyton Manning and the Broncos in the playoffs.

3. Saving their jobs: Last week, Miami Dolphins owner Stephen Ross surprised everyone by saying Joe Philbin will be back as head coach next year. On Sunday, Falcons coach Mike Smith will be battling for his job. The odds of him returning aren't good, but he could increase them by reaching the playoffs. Just winning the NFC South with a 7-9 record might not persuade the Falcons to keep Smith. Nevertheless, a win could create a home matchup against the Cardinals, who might not have Drew Stanton and lost in Atlanta in Week 13. Smith could change the equation by getting to the divisional round. If the Falcons win Sunday, they'll be 6-0 in divisional games and 1-9 against the rest of the league.

Black Monday likely will involve Rex Ryan of the New York Jets, Tony Sparano of the Oakland Raiders and possibly Marc Trestman of the Chicago Bears. It probably doesn't help Trestman that Jay Cutler is back at quarterback for the finale after being benched last week. Jimmy Clausen has a concussion and can't play against Minnesota. The Jim Harbaugh situation with the San Francisco 49ers could be resolved within a few days of the season's end. With the Dolphins out of the running, he could end up at Michigan (his alma mater) or move to the Raiders. The decent finish by the New York Giants, who are on a three-game win streak, probably kept Tom Coughlin off the chopping block. The Giants close out against Philadelphia.

4. Key games to watch: NBC grabbed Cincinnati-Pittsburgh for its prime-time slot because the rivalry game will determine who wins the AFC North. The Steelers have won seven of their past nine games against the Bengals, and Mike Tomlin is 11-4 against Marvin Lewis. The next-best game is Detroit at Green Bay, where the Packers have a great advantage. The Lions haven't won at Lambeau Field since 1991. Arians will test out rookie Logan Thomas against the 49ers to see whether he could help the Cardinals in a playoff game if Stanton isn't recovered from a knee injury. Ryan Lindley was awful Sunday night in Arizona's loss to Seattle.

5. The impact of injuries: By my count, starters missed 1,635 games because of injuries in 2013. That number will exceed 1,800 this year, and that doesn't include the 105 starts missed because of suspensions or commissioner exemptions. Despite losing three quarterbacks, the Texans had the healthiest team with only 35 missed starts, a number matched by Green Bay. Pittsburgh was next with 36. (The totals here were calculated through Week 17 to account for players on injured reserve, but they could change if there are active players who can't go Sunday.)

Chuck Pagano did a great job of navigating the Colts through a season in which they lost Robert Mathis for the year to a suspension and an Achilles tear and had a league-worst 93 missed starts because of injuries. From 2011 to 2013, the 49ers had a total of only 72 missed starts. Their recent seasons lengthened by successful playoff runs appear to have caught up to them. They've lost 78 starts because of injuries this season and were without linebacker Aldon Smith for nine games because of a suspension. Baltimore, Buffalo and Detroit were all in the low 40s, which certainly is a factor in their improved records. The New Orleans Saints (41) and New York Jets (41) didn't take advantage of healthy seasons and had significant drop-offs this year.