1. Denver Broncos

The more you look at it, the more this seems like a championship-or-bust season for the Broncos. They have the best defense in the NFL according to our PFF grades, and a good offensive supporting cast, but Peyton Manning looks like a quarterback finally at the end of his outstanding career.

Manning ranks just No. 31 in PFF’s QB grades this season, seeing a drop-off in his performance across the board (he has the second-lowest accuracy percentage in the NFL, after years of ranking near the top of that metric) and is currently missing time with a partially torn plantar fascia. His replacement, Brock Osweiler, has gone 3-0 as a starter since taking over, but don’t let the record fool you: He has graded as a below-average QB over those three outings, and his drop in passer rating of 61 points when the opposing pass rush gets to him is a major red flag (the NFL average is a drop of 27 points).

The team will need to evaluate quickly whether it views Osweiler as a long-term fix at the position, if Manning doesn’t return for the 2016 season, as Osweiler is an unrestricted free agent this coming offseason.

2. Cleveland Browns

Josh McCown ranks as PFF’s No. 27 quarterback this season, while Johnny Manziel ranks No. 33.

Manziel at least offers some upside. He can make plays as a runner, has shown the ability to stretch the field as a passer (6 of 10 on deep balls this year) and, despite being under pressure often, has handled opposing pass rushes relatively well. He is coming off the best game of his career in his last start against the Steelers.

On the other side of the ledger, off-field concerns have disrupted his career, he has yet to prove he can consistently beat defenses from the pocket and, unless he puts together a very impressive four-game stretch to end the season, chances are high the Browns will consider taking a quarterback with what will likely be a top-five pick in the 2016 NFL draft. The two names being brought up right now as top QB prospects are California’s Jared Goff and Memphis’s Paxton Lynch, but our college data prefers Goff. He earned the second-best passing grade among Power-5 conference players this season despite a limited supporting cast, and while his decision-making is a question mark, his ability to succeed against pressure and make difficult downfield throws was apparent in our grading and will likely stand out to evaluators during draft season.

3. Washington Redskins

Kirk Cousins is a free agent after the 2015 season, and whether he is back with the team in 2016 could depend a lot upon how Washington finishes the season and whether it wins the NFC East. Regardless, Cousins is likely to get a lucrative long-term contract from a team, even if it isn’t the Redskins, given the dearth of quality play at the position league-wide.

Should Washington re-sign him? He has ranked as just PFF’s No. 21 QB this year, and he has posted some pretty concerning numbers in two key areas. When facing pressure this season, his passer rating has dropped 56 points. That isn’t good. Neither are his deep-passing numbers. He has completed just 11 of 46 throws of 20-plus yards this season. It’s certainly true that the team could do worse, and being left to find an upgrade in free agency or the draft could prove difficult.

But Washington fans shouldn’t view re-signing Cousins as a surefire path to the Super Bowl either.

4. Philadelphia Eagles

Sam Bradford will likewise hit free agency after this season, and there’s added uncertainty in Philadelphia related to whether Coach Chip Kelly, who is also overseeing personnel decisions, will be back with the team in 2015.

Bradford has played relatively well in his one season with the Eagles, ranking as PFF’s No. 14 quarterback. His performance when facing pressure has been impressive, with a QB rating above the NFL average, and he has fared well overall despite having the lowest-graded receiving corps in the league. His situation isn’t all that dissimilar to that of Cousins – he isn’t an elite QB, but he might be the best option his team has. And no matter what, he figures to receive a big contract this offseason.

5. San Francisco 49ers

Colin Kaepernick appeared to be a 49ers lifer after signing a six-year, $114 million contract extension last offseason, but the truth is the team structured the contract in such a way that it could move on from Kaepernick with less of a financial penalty than a team normally could on a deal that size, and there’s a good chance the team could let him go before April 1 this coming offseason (despite recent media reports that the team is interested in bringing him back).

Kaepernick had an awful season before undergoing season-ending shoulder surgery, recording the worst accuracy percentage vs. pressure in the NFL. And while Blaine Gabbert has been okay since taking over the starting job, it wouldn’t be at all surprising if San Francisco had a new starter in 2016.

It will be very intriguing if the Niners wind up with a top-five pick and local product Goff is on the board.