The Must-December Team: Players, coaches with most on the line now

Browns need to find out about Manziel (1:42)

With Josh McCown out for the season, the NFL Insiders crew agrees the Browns should start Johnny Manziel at quarterback because they need to find out if he's the answer. (1:42)

With just five weeks of football left on the NFL calendar, most players have already made their mark in terms of how observers will look back at their 2015 campaigns. It'll go down as a great year for DeAndre Hopkins and a terrible one for Ryan Tannehill. At the extremes, it's going to be exceedingly difficult for players to re-write their 2015 story.

There are a fair number of players and coaches around the league, though, who could have their short- and long-term professional futures defined by what happens to them over the remainder of the regular season (and, if applicable, the playoffs to come). What they do between now and February might very well mean more than what has happened over the first three months of the season. They're the Must-December Team.

You can probably figure out which sorts of personnel will be appearing here. The most obvious subset would include players who are about to hit unrestricted free agency -- think about the likes of Byron Maxwell and Paul Kruger when it comes to recent players who have cashed in on short stretches of above-average play.

With that being said, there are a number of pending free agents who have already played so well that they don't need to be included here. That group consists of players such as Von Miller, Josh Norman and Muhammad Wilkerson, stars who will earn top-dollar contracts (or be slapped by the franchise tag) as long as they don't suffer career-threatening injuries over the next few weeks. Even if Miller doesn't record a single sack between now and March, he's going to receive a Clay Matthews-esque contract this offseason.

Let's run through some notable candidates for the Must-December Team. What do they need to do to head into the offseason on a high? And what will that mean for their careers? This starts in Miami:

Dan Campbell, Coach, Miami Dolphins

The honeymoon period for Miami's interim coach is over. After promising to rebuild the Dolphins around toughness and a power-running philosophy, Dan Campbell won his first two games by a combined 46 points. Since then, he has gone 1-4 and been outscored by 72 points, with his lone win against the struggling Eagles by one point. Campbell's Dolphins have practically abandoned the run, with Lamar Miller and Jay Ajayi combining for eight yards on eight carries during Sunday's blowout loss to the Jets. Campbell promptly fired offensive coordinator Bill Lazor after the game.

Campbell would likely keep his interim gig if the Dolphins made the playoffs, but that's a near-impossibility at this point; at 4-7, ESPN's Football Power Index (FPI) gives Miami just an 0.4 percent shot of making the postseason. Campbell's best hope is for Miami to sweep its remaining five games. That's also incredibly unlikely, but less out of the question. Four of the Dolphins' five remaining games are at home, and with the Ravens, Chargers and Colts still to come, their schedule does not look particularly imposing. Their toughest matchup comes against the Patriots in Week 17, but Bill Belichick may very well be resting his players if the Pats lock up home-field advantage in Week 16. FPI gives the Fins a 2.0 percent chance of finishing 9-7, but with the possibility of facing Matt Schaub, Matt Hasselbeck and Jimmy Garoppolo in their games to come, Campbell may have a better shot at earning the permanent job than the numbers suggest. Even a 4-1 finish might be enough.

Johnny Manziel, QB, and Gary Barnidge, TE, Cleveland Browns

I probably don't need to explain why Johnny Manziel's on the precipice right now. Having been benched for another off-field incident, Manziel's status with the Browns organization is tenuous at best. When he has played this year, though, Manziel has shown flashes of why the Browns took him in the first round of the 2014 draft, even if a deeper tape review has revealed some ugly truths.

In this case, what Manziel does over the remainder of the season might be less about impressing the Browns and more about impressing possible trade suitors. As damaged as Manziel's stock might seem, there will always be NFL coaches who believe they can break through to a top passing prospect and turn him into a viable starter. Teams have traded draft picks for Blaine Gabbert and Sam Bradford in recent years. If Manziel flashes some hopeful signs and literally stays inside his house when he's not at the practice facility, it might be enough for him to end up in a better situation in 2016.

People who might not want that to happen? Manziel's top receiver, Gary Barnidge, is about to hit unrestricted free agency and might very well prefer Austin Davis, who was impressive late against the Ravens on Monday night. The 30-year-old Barnidge is likely to receive his first and only significant contract this offseason, and his pro-rated line since Week 3 for a full season is ridiculous: 91 catches, 1,250 receiving yards and 12 touchdowns. Julius Thomas picked up $24 million guaranteed after being a dominant red-zone weapon for two seasons with Peyton Manning in Denver. Barnidge won't get that sort of deal, but if he can keep this pace up, some tight end-needy team -- look toward New York -- is going to pay him. And it may be easier to keep that pace up with Manziel on the bench.

Jason Pierre-Paul, DE, New York Giants

Speaking of New York, Jason Pierre-Paul has been mostly anonymous since returning from his offseason fireworks accident. In three games, JPP has no sacks and one lone tackle for loss. The Giants' pass rush has floundered in the meantime, taking down opposing quarterbacks on 2.7 percent of dropbacks in 2015, the lowest rate in football.

Obviously, it's impossible to determine how teams will dock Pierre-Paul now that he's down a finger; given that the Giants are the only team to medically examine JPP since the incident, any possible suitor will want to give the star edge rusher a lengthy physical before committing serious money. And it's also true that Pierre-Paul is still returning to game shape after sitting out for the first half of the year. If he continues to struggle, though, the lack of production after the accident and the existing concerns about his back (which required surgery two years ago) may cause teams to disqualify Pierre-Paul from offseason consideration.

Greg Hardy, DE, Dallas Cowboys

Another 4-3 defensive end from the NFC East, Greg Hardy's on this list for entirely different reasons. There will be many teams who find Hardy's off-field history and attitude distasteful enough to look elsewhere, but don't pretend for a moment that the Cowboys were the only team interested in Hardy this offseason. The fact that Dallas gave Hardy a one-year deal worth at least $10 million if he stays healthy should tell you the Cowboys were competing with other teams for Hardy's signature.

While Dallas is all but eliminated from the playoff picture, Hardy has much to play for. With 4.5 sacks over seven games, he needs 3.5 more to make it to eight and earn a $500,000 incentive; a 10-sack campaign would kick in an additional $500,000. And if Hardy continues to produce, more teams will be inclined to look away from Hardy's abhorrent behavior and justify a long-term outlay for one of the league's best pass-rushers.

Doug Martin, RB, Tampa Bay Buccaneers

A Comeback Player of the Year candidate, Doug Martin has been an awesome force and arguably the most important part of a resurgent Buccaneers offense. Behind an anonymous offensive line, Martin's averaging 5.1 yards per carry on his first 202 totes of the 2015 campaign. He lacks the pure top-end speed to accelerate away from defenders in the open field, which is why he's caught from behind on so many runs, but Martin has been showing off decisive cuts, impressive vision and remarkable patience as a runner all season.

It will be tough for a team to value Martin going forward as the player he has been in 2015. DeMarco Murray was an injury-prone player who had been impressive throughout his run in Dallas; Martin was both injury-riddled and ineffective with the Bucs during the 2013 and 2014 seasons. If he stays healthy and impactful, though, Martin should be able to exceed the three-year, $11 million deal Ryan Mathews earned from the Eagles this offseason, if only because his breakout season came just before free agency, while Mathews was a year removed from his.

Jeff Fisher, Coach, St. Louis Rams

As rumors whirl about his team's future in St. Louis, Jeff Fisher has seen his Rams collapse. The Rams have dropped four straight games, and FPI leaves them with just a 1.4 percent chance of making the playoffs. St. Louis is entering a three-game homestand against the Cardinals, Lions and Buccaneers that was supposed to make or break their season, but after a 1-4 November, St. Louis's campaign may very well be shattered beyond repair.

Fisher's job may already have been lost in the shuffle. The best-case scenario for him, much as it is with Campbell, is to sweep the rest of the way. Given that the Rams still have to host the Cardinals and travel to Seattle, that seems unlikely. And if he doesn't make it there, chances are Fisher will be as good as gone. He has yet to post a single winning season (or even an 8-8 campaign) with the Rams. The last time a coach went four years without posting a winning record and held onto his job? 1998, when the Tennessee Titans held onto ... Jeff Fisher.

Sam Bradford, QB, Philadelphia Eagles

Let's finish with a series of quarterbacks who have as much at stake financially as anybody in football. It seems like another lifetime ago, but it was only early September when Sam Bradford and the Eagles reportedly cut off negotiations on a short-term contract extension because Bradford had shined so brightly during the preseason.

Since then, it has been a mess. The former No. 1 overall pick has had the same issues throwing downfield that stifled him during his Rams days, while the one thing it seemed safe to count on -- his ability to protect the football -- has disappeared. Despite throwing the league's third-shortest passes, with his average throw going just 6.9 yards in the air, Bradford has thrown picks on 3.0 percent of his pass attempts, the sixth-worst rate in football. Apart from that second half against the Falcons in the opener, he has been arguably the worst quarterback in football.

Bradford's hopes of signing a contract in the Colin Kaepernick/Andy Dalton tax bracket this offseason are gone. At this point, Bradford's best-case scenario is (ironically) something like the extension Nick Foles signed with the Rams, a team-friendly two-year deal that guarantees a small amount of money in 2016 without really making any serious long-term commitment. Expected to make his return from a shoulder injury this weekend, the most plausible way Bradford gets there is by slicing his interception rate back to or below where it was with the Rams (2.2 percent) while staying healthy. Or convincing the rest of the league to play defense like it's the preseason.

Brock Osweiler, QB, Denver Broncos

The jury's still out on Brock Osweiler, but you can certainly say that he has managed to pass through his first two professional starts without seeming overwhelmed by the job. He has thrown only one interception during those two starts, which is a nice change of pace after Peyton Manning threw 17 in nine games. The Denver rushing attack certainly looks better with Osweiler operating from under center (as coach Gary Kubiak believes nature intended) versus what Manning was doing in the pistol, but some of that is likely opponent-related. The Broncos gashed the Bears, who have the league's second-worst run defense, and only found a spark against the Patriots after Dont'a Hightower went down with a knee injury.

Under any circumstances, Osweiler's been impressive enough to justify holding onto the starting role for the remainder of the season. What he does over that stretch has the potential to be very lucrative. The Broncos decided against signing Osweiler to a contract extension before the season, meaning that Osweiler will finish up his rookie contract and become an unrestricted free agent after the year. Denver could give Osweiler a massive raise of more than $20 million and stick him with the franchise tag, but that would preclude them from applying the tag to Von Miller, who also needs a new deal. The Broncos can clear $19 million off of their 2016 cap by moving on from Manning, but a one-year deal probably won't be enough if Osweiler plays well. If he looks like a viable starting quarterback into and through the postseason, Osweiler is going to have as much leverage as any player in football. And make no mistake: the most important factor in determining how much a player is going to make is not talent. It's leverage.

Kirk Cousins, QB, Washington

Kirk Cousins just finished the best five-game stretch of his career. Starting with Washington's comeback win over Tampa Bay, Cousins has thrown just two interceptions in five games. Before this run began, Cousins' best five-game stretch as a starter had included five picks. He has posted a 111.5 passer rating over that time, which is tops in football. QBR isn't quite as impressed -- Cousins' 67.3 figure is 12th in the league since that Bucs game -- but when the 12th-best quarterback in the league is making $660,000, as Cousins is this year, that's a really valuable asset.

Everything for Cousins comes down to that interception rate, which was the highest in league history after adjusting for era heading into the season. It would be foolish to take Cousins's last 164 pass attempts and use that as proof that he has permanently changed, but it would also be naive to point to Cousins' past and say that there's no way he could possibly grow as a quarterback.

The truth, as always, is somewhere in the middle. If Cousins' final five games of the year look like the player he has been since the second half of that Buccaneers win, Cousins is suddenly a 27-year-old quarterback hitting the free-agent marketplace looking like he has solved his biggest problem. That guy doesn't look all that much different from Jay Cutler, who earned $54 million guaranteed when he hit the market at age 31. And if he throws nine picks and looks like the same old Cousins, maybe the former Sparty star gets to ride the Brian Hoyer carousel and end up in Cleveland or Houston on a one-year deal for, say, $6 million? No pressure.