Just as important as filling a roster with skilled players is keeping that talent healthy.
In no place is that more apparent than the AFC North, which pretty much already has been decided by who has avoided sick bay.
Baltimore is languishing at 2-6 in part because of an epidemic that has cost the Ravens their top defensive player, linebacker Terrell Suggs, and their one elite receiver, Steve Smith. Baltimore has 12 players on injured reserve and, shockingly considering its history for nearly two decades, is in the running for the top overall draft pick.
''You move on, That's what you have to do,'' coach John Harbaugh says. ''It never changes. We're never going to use excuses, we're never going to say that we don't have enough firepower or enough ammunition. We're never going to say that because we don't believe it. We always believe that we've got players in the pipeline that can get the job done.''
Cleveland also has been ravaged. Quarterback Josh McCown's gutsy display on the field despite a shoulder problem was admirable, if somewhat counterproductive. Star cornerback Joe Haden is battling concussion issues, as is safety Donte Whitner. Coach Mike Pettine is fortunate if he can find 11 supposedly healthy players to start on defense.
Then there's Pittsburgh, which saw Le'Veon Bell, its 2014 All-Pro running back, go out with a torn-up knee in Week 8. Now, it's QB Ben Roethlisberger, who already missed four games with a knee issue and hurt his left foot on Sunday. He's gone for at least one game, and with the Steelers at 5-4, that's a huge deal for their playoff chances.
Pittsburgh has remained competitive because of an improved defense, the magnificence of receiver Antonio Brown, and the timely signing in the offseason of DeAngelo Williams as a backup to Bell. But such major injuries eventually catch up to teams, and the Steelers still have Seattle, Indianapolis, Cincinnati and Denver on the schedule.
Of course, injuries have not been limited to that division, and several presumed contenders have flopped in great part because of them.
Dallas (2-6) is Exhibit A, with Tony Romo's collarbone following Dez Bryant's broken foot. Bryant is back, Romo will be by the end of the month, but not linebacker Sean Lee, the defensive leader, who is dealing with concussion issues. Even before Bryant and Romo went down, top cornerback Orlando Scandrick was lost for the season with a torn ACL.
Another prime example is Buffalo, which is at .500 despite a slew of problems, mostly to the offense. QB Tyrod Taylor (knee), receivers Sammy Watkins (ankle/hamstring), Percy Harvin (knee and hip and now done for 2015) and Marquise Goodwin (ribs), and RBs LeSean McCoy (hamstring) and rookie Karlos Williams (concussion) have been sidelined at various times.
Some teams have the good fortune of getting back some key performers. Giants DE Jason Pierre-Paul, who blew off a finger and damaged his right hand in a July 4 fireworks accident, made his regular-season debut Sunday.
As we move into the stretch drive, here's a look at other injuries that could have the biggest effect on the playoff races.
LB DEMARCUS WARE, BRONCOS - A balky back could plague one of the leaders of Denver's staunch defense, and disrupt the pass rush.
DE CHARLES JOHNSON, PANTHERS - He's on short-term IR and could bolster an already solid, big-play defense on the NFC's only unbeaten team.
OT JASON PETERS, EAGLES - No one wants to lose their blind-side quarterback protector.
OT NATE SOLDER, and RB DION LEWIS, PATRIOTS - Ditto for the Patriots, except they find ways to plug in linemen. Running backs, too, but replacing the versatility shown by Lewis could be difficult.
C NICK MANGOLD, JETS - The most efficient Jets blocker has been slowed by neck issues. Not good on a run-oriented team.
LB ALEC OGLETREE, RAMS - St. Louis' most versatile defender should return by the end of the season. Will the Rams still be in the wild-card race?
DT HARRY ANDERSON and DE ARTHUR JONES, COLTS - Anderson was a revelation as a rookie, and Jones will continue being missed in the trenches.
RB ARIAN FOSTER, TEXANS - A team with uncertain quarterbacking can't afford to lose its top runner.
QB TEDDY BRIDGEWATER, VIKINGS - Minnesota's turnaround could be short-circuited if Bridgewater's concussion sidelines him for a while.
RB JAMAAL CHARLES, CHIEFS - Kansas City is on the periphery of the wild-card chase, but not likely to stay there minus its best playmaker.
DE CAMERON WAKE, DOLPHINS - Miami also is a long shot for the postseason, and Wake's injury really lengthens the odds.
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