Kirk Cousins walks off the field after the final play of the Redskins’ home opener. (Toni L. Sandys/The Washington Post)
Columnist

To complete our degree in quarterback nitpicking, we have to get through one final course this season. Call it “Eclipsing Failure 408.” If we want to be experts at scrutinizing Kirk Cousins — our crazy, excessive and often petty pastime — we need to see him fail, see him lose control more than he has the past two games or even past two seasons. And then we need to watch how he reacts.

Watch closely because that will serve as the capstone lesson in both his quarterback education and our understanding of his true value. Franchise quarterbacks aren’t just defined by success under ideal conditions. Good lord, Cousins knows that by now. If throwing for 4,917 yards last season — the 15th-most prolific passing performance in NFL history — didn’t eliminate concern, there’s not much else Cousins can do. Except outlast failure.

The finest signal-caller connoisseurs will tell you that they prefer to judge a quarterback by his ability to play through struggles, accept imperfection, manage chaos and still win in the end. There’s a belief that, no matter how bad the situation, a good quarterback can make it right. It’s assumed that franchise quarterbacks will put up ridiculous stats most of the time, and Cousins has done that for the better part of two seasons. But what happens when they don’t? Can they stand out in the mud, when the defense is too good or the offense is too bad, when the line collapses and pass rushers batter them, when receivers drop passes and hope seems absent? The real franchise-carrying talents can.

Assuming the Washington Redskins don’t transform magically into an offensive juggernaut against Oakland on Sunday night, Cousins will receive plenty of opportunities this season to show that he has evolved into that kind of player. The first two games have served notice that this journey could be a slog. Cousins won’t be chasing 5,000 passing yards in 2017. But if he can lead Washington to another winning season and do so the hard way, he might convert some of the remaining detractors.

That doesn’t give him permission to play poorly and receive a pass if the team wins in spite of him. The challenge is that it will be harder for Cousins to play well than it has been during any time since he was named the permanent starter in 2015. His revamped receiving core is raw and needs time. Despite 229 rushing yards last week against the Los Angeles Rams, the running game is just as much of a work in progress. The defense is, too. It’s still vital for Cousins to feel comfortable and play within himself, but the team around him can’t protect him as much as it once did.

Over the past two years, Cousins has redefined his status and made almost $44 million playing on franchise-tag contracts. To get to this point, he has shown plenty of persistence and mental toughness. He’s not fragile, never was. That was a misconception caused by a small sample size during his developmental phase. But defeating low expectations is a basic achievement for a player who wants to have a long career. It’s a more advanced task to raise the bar under the current conditions.

In the season-opening loss to Philadelphia two weeks ago, Cousins failed. It wasn’t entirely his fault, but he committed three turnovers, including a controversial fumble late in the fourth quarter that Eagles defensive lineman Fletcher Cox returned for a touchdown. Last week in Los Angeles, Cousins transcended several moments of failure by protecting the football and not making any game-changing mistakes, staying patient and playing his best at the end. He completed all three of his passes on Washington’s most important drive, and he threw an 11-yard touchdown pass to Ryan Grant with 1:49 remaining to win the game. His stats looked ordinary: 18 for 27 for 179 yards and a touchdown. Several times last season, he threw for that many yards in a half. But he did what he had to do to win.

“I liked the way he finished,” Coach Jay Gruden said of Cousins. “That’s the most important thing. Getting a win on the road is not easy, anywhere, any time. And making the key throws down the stretch, going 3 for 3 on that last drive, was critical.”

What is required for Washington to win is a fluid concept. The team has no established strengths. Quality offensive line play should be a constant, but that unit is just starting to play well. The tight end tandem of Jordan Reed and Vernon Davis is special . . . when Reed is healthy. No other position group has a long enough record of continuity and high performance. There are plenty of good individual players, but the team is in search of overall stability. That’s not the best way to build around Cousins long-term, if that’s what the franchise intends to do. But Cousins still must find a way.

“I think the beautiful thing is when you win the game, you can watch it and say, ‘Okay, that’s a place to get better,’ but it doesn’t hurt quite as much, because you know it didn’t cost you the game,” Cousins said. “When you lose the game, that’s where watching those plays just eats at you. Getting the win healed a lot of that. There will be plays up ahead — lots of games are left, thankfully — and we’ll get a lot of opportunities. I’m excited to watch our players and our offense, including myself, develop and improve. I expect us to be a more mature offense, a better offense, in Week 15 than we are in Week 3.”

Through two weeks, Cousins is averaging 209.5 passing yards; he averaged 283.8 the past two seasons. His passer rating is 82.9; it was 99.3 the past two seasons. At least Cousins can find confidence in knowing that he has a history of playing better as the season progresses.

You have seen what he can do when blessed with some of the league’s best offensive players. But can he hang in there and make this group better? Washington has good but unrefined offensive talent this season. You have a quarterback who depends on the whole and offensive weapons that are more dependent on the quarterback. You can see the potential for disaster. But it would be foolish to write off a player who has come this far.

“I think there is more in the tank there that we have got to bring out,” Cousins said.

As we have become smarter and more stat-driven in analyzing sports, the plain old label of winner has lost its significance. The notion of “quarterback wins” has been battered. No longer is a ratty QB on a great team given gratuitous credit if advanced numbers show he’s merely leeching off the success.

But when you’re talking about quarterbacks who produce and trying to separate them with fine lines, intangibles still matter. They all fail at some point. The position is too hard; the responsibilities are too great. But who can transcend the chaos and still play winning football? Is Cousins anywhere near that level?

For him, that might be a $100 million question. The inevitable struggles of this season will define the player Cousins truly is.

For more by Jerry Brewer, visit washingtonpost.com/brewer.