While some think Redskins quarterback Kirk Cousins is merely above average, the numbers show he may be elite. (0:30)

Editor's note: This story was originally published before the Redskins and Cousins failed to work out a long-term deal by Monday's deadline.

The Washington Redskins may not know how good they have it.

As the team attempts to lock up quarterback Kirk Cousins to a long-term deal, the rhetoric emanating from the NFC East franchise suggests a belief that their signal-caller is merely an above-average passer. The numbers say that's selling him short.

"Kirk has proven he's in the top 15 quarterbacks," Doug Williams, now the Redskins' senior vice president of player personnel, said recently. The comment wasn't meant as a slight (and may have been a negotiating tactic), as Williams has indicated that he certainly wants to lock Cousins up to a new deal.

Former general manager Scot McCloughan indicated in May that he felt Cousins had reached his ceiling and that the quarterback needed to be surrounded by other talent. Though McCloughan is now out of the picture, his sentiment appears to be a popular perception of Cousins -- a solid but unremarkable quarterback. The advanced metrics paint a different picture, one of an upper-tier passer who probably deserves the higher compensation he seeks.

You like that? The Redskins apparently can't decide, despite data suggesting they should lock up Kirk Cousins. Kamil Krzaczynski/USA TODAY Sports

Despite a two-interception performance in a Week 17 loss to the New York Giants that cost the Redskins a playoff berth -- more evidence for Cousins' detractors that he's prone to the late pick -- he finished the 2016 season with a Total QBR of 71.7, sixth best in the league. It was not a fluke: He finished in the exact same position the year before. Over the course of 2015 and 2016 combined, QBR ranked him fourth, behind only Dak Prescott (in a one-year sample), Tom Brady and Matt Ryan. To repeat: A two-year sample and Cousins was safely in the company of Brady, Ryan and arguably the best rookie quarterback season in history. People get paid for less.

Though there are some instances when analytics reveal hidden talents, the reality is that much of Cousins' abilities have been viewable in plain sight: He was the leader of the offense that recorded the second-most passing yards in 2016 while throwing for the third-most yards per attempt (8.1) among quarterbacks.

Total QBR is not the only advanced metric indicating that Cousins is better than the level Williams referenced. In Football Outsiders' DVOA, Cousins ranked sixth and fifth, respectively, among quarterbacks in 2015 and 2016. He finished eighth and fourth, respectively, in those two years in Pro Football Reference's adjusted net yards per attempt as well.

Certainly, there were a couple of specific areas in which Cousins excelled, as would likely be the case for any quarterback to rank so highly in QBR. Most notably, the Redskins quarterback leaned more heavily on, and had more success with, the deep ball in 2016. Though he finished fourth in raw QBR (which does not adjust for quality of opponent) on passes that traveled 21 or more yards in the air in 2016, he did so on the second-most attempts (69) and therefore contributed more expected points (24.55) on those types of passes than any other quarterback in the league. Ben Roethlisberger ranked second in the category, finishing with 20.57 expected points added on those throws.

While QBR does try to isolate the quarterback's impact on each play, it is worth noting that part of the reason Cousins had the opportunity to throw that many passes downfield is because he had DeSean Jackson on his team. Jackson had the second-most targets (30) and receptions (14) on passes that traveled 21-plus yards in the air last year and ranked third in air yards per target. Cousins will not have the benefit of throwing to Jackson again this season, as the receiver bolted in free agency for Tampa Bay, though Terrelle Pryor Sr. -- 10th in air yards per target last year with far inferior quarterbacks throwing to him -- was signed in his stead.

Additionally, Cousins was at his best, relative to other quarterbacks, when not under pressure, leading the league in 2015 and finishing fourth in 2016 in raw QBR when not under duress. Of course, the flip side of Cousins' success when not under pressure is that he was particularly poor with it. He ranked 30th and 21st in raw QBR when under pressure in 2015 and 2016, respectively, and 17th and 16th when facing five or more pass-rushers in the same time period. Interestingly, opponents did not overly capitalize on this relative weakness, as Cousins was blitzed on only 24.6 percent of dropbacks (16th most) in 2016.

Nonetheless, if the Redskins are hoping to pay Cousins at the rate of a top-15 quarterback, they are probably being optimistic given the numbers the former fourth-round quarterback has put up over the past two seasons.

In March, ESPN reported what is still the latest known offer from the team to the quarterback -- a $20 million per year deal that spanned five years with "low" guarantees. (The MMQB later added that the offer was actually an extension on top of the 2017 franchise tag). Cousins' camp sought a deal starting at his 2017 franchise tag salary of close to $24 million.

A contract with an average annual value (AAV) of $20 million would slot him below 13 quarterbacks in the NFL, per OverTheCap.com. Even if Cousins were only the 14th-best passer in the league, that AAV would be well below market value for him given that all 12 of the 13 quarterbacks on that list -- Derek Carr excluded -- signed their deals in earlier years, when the salary cap was lower.

It's tempting to compare Cousins' situation to Carr's given that the Raiders quarterback recently signed a five-year extension that ESPN reported included $125 million in new money. But frankly, Cousins holds much more leverage than Carr had given that he's already been hit with the franchise tag twice. The Redskins quarterback could look to parlay that leverage into more than the $40 million fully guaranteed that Carr received at signing.

On top of that, Cousins has played at a level far superior to Carr over the past two seasons. While Cousins ranked fourth in Total QBR over 2015-2016 combined, Carr finished 26th in that same span. Even looking at only 2016, Carr ranked 16th, lagging well behind Cousins at No. 6.

Granted, QBR reflects only how well Cousins did play, rather than how he will play, which is probably what the Redskins care about when making a contract offer. But given that he is just 28 years old and finished sixth in the metric two years in a row, there is little reason to think his performance going forward shouldn't be near that mark.

In the end, the offer from the Redskins may not matter, as ESPN recently reported that there is no number from the Redskins that would make Cousins happy. If Cousins ultimately ends up leaving Washington at the end of this saga, the Redskins will be letting a very good quarterback walk out the door.

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