When Bears quarterback Mitchell Trubisky went from John Fox to Matt Nagy, it was like trading in his Betamax for 4K, and he didn’t even have to be shamed into it by the curly-haired kid from Stranger Things. With the Bears sitting in first place in the NFC North and the Packers firing their head coach while clinging to their playoff lives into December, we’re already in the upside down.

To get there, Chicago has had to score points, nearly 29 points per game, even with the top defense in football. It’s been Trubisky’s development in Year 2 with Nagy that’s allowed the Bears to do that and pushed them into the top tier of NFC contenders. The coaches trust him now, not just to execute calls, but to play with confidence. To be himself.

The cerebral and charismatic 40-year-old coach worked under Andy Reid with the Eagles before following him to Kansas City where Nagy spent three seasons as quarterback coach and two as the offensive coordinator. There was no guarantee Nagy’s arrival in Chicago would be able to successfully implement the type of creative, entertaining and terrifyingly effective offense the Chiefs had with Alex Smith and now with Patrick Mahomes.

And no one in Chicago is ringing the bell more for collaboration with the quarterback than Nagy, setting up a perfect incubation system to grow with an inexperienced quarterback. Rather than drilling a quarterback to do something he can’t, design an offense around what he can execute.

“We’re always looking for feedback from [Trubisky]” Nagy said as he prepared his team to face the Lions earlier this season. “And right now we’re starting to feel comfortable with a select group of players, how it fits, and concepts for certain players.”

Bears GM Ryan Pace believed a coaching change wouldn’t suffice, spending big in the offseason to bring in ex-Jaguars receiver Allen Robinson and versatile former Eagles tight end Trey Burton, along with spending a second-round pick on receiver Anthony Miller. Part of the Chiefs’ success stands on having arguably the best skill talent in football. Without talent, those progressive schemes would be like driving a sports car without a transmission. It looks nice, but it’s hard to get where you want to go.

Upgrading scheme and personnel would help put Trubisky in a position to succeed, but he still needed to be empowered by this coaching staff.

In 12 starts a rookie, Trubisky only threw for more than 200 yards three times and never threw more than a single touchdown in a game. The Bears looked afraid to let Trubisky throw the ball at all and when he did, found the dirt or the other team too often. He was near the bottom of the league in average intended air yards with players like Blake Bortles, Brock Osweiler and Josh McCown. A successful NFL offense can’t be built solely on underneath throws.

Alex Smith may have been the ideal test run for Nagy, as the Chiefs took the notoriously conservative veteran and got him taking downfield shots last season. It would have been easy to insist Trubisky was the same kind of conservative quarterback. In fact, the idea of playing it safe was so ingrained in Trubisky, his new coaching staff had to literally coach it out of him.

“We threw a lot at him in training camp and he handled it really well,” Nagy says. “The success because there were some failures within the learning process ... I was OK with it. There were some interceptions. We were trying to teach him how to be aggressive and throw downfield. I think we broke that pattern and now he’s good there.”

That’s no direct shot at Fox and his staff, nor is Nagy implying one, but the circumstances suggest an indictment of the old regime. Trubisky’s quarterback coach Dave Ragone says the player we’re seeing this season is the player he’s been since high school with wide-open offenses and wanting to air it out. In other words, last season was the out-of-character year for Trubisky -- not this one. The coaches just had to re-empower him to be himself after a season of playing not to lose.

Nagy insists that process was a team effort by all the offensive coaches and the backup quarterbacks, each of whom have spent more seasons in the NFL than Trubisky. Reforming habits, reminding Trubisky it’s not only acceptable but suggested to take a shot where it’s called for, wasn’t a hard sell. The Bears just needed their quarterback to receive the message and implement it.

“When you’re teaching it, you’re showing it on tape and you’re reminding him all the time if there’s a play call with a shot involved, go ahead and take it,” Nagy explains.

“And this went back to training camp where the risk isn’t as big for going downfield and having an interception in practice. You’re seeing, No. 1, which wide receivers can you trust that it’s not going to be an interception. And No. 2, you’re testing out where you’re at with your timing and your drop to them. That part’s actually easy as a coach because as a quarterback when you’re being told to throw the ball down the field and test it, most quarterbacks want to do that and he’s one of them.”

That work in the spring and summer paid off in an impressive way for the Bears and Trubisky.

Among quarterbacks who have started at least eight games, no one has consistently thrown the ball further downfield than Trubisky, who leads the NFL in intended air yards. (Intended air yards measures how far downfield the ball travels in the air, helping account for quarterbacks who rely on short passes for put up big numbers).

Critics will point out the creativity in Nagy’s scheme helps Trubisky, the same way Reid’s does with Mahomes or Sean McVay’s with Jared Goff. Give quarterbacks easier throws with big throwing lanes, and of course the quarterback will be able to create big plays. But according to the NFL’s Next Gen Stats, Trubisky ranks fourth in what they call aggressiveness percentage in that same cohort of starters, which means he’s making throws into tight windows about 19 percent of the time. That signals not everything from this Bears offense has come easily, despite excellent play calling and design. Trubisky is not only slinging it down the field, he’s not having to throw to wide-open receivers to see windows. Trust and aggressiveness. These are clear signals that the message about trying to make a play without worrying about mistakes has been received.

On the other hand, Trubisky has led the league in off-target throws most of the season according to ESPN’s stats, missing his spot on more than 21 percent of his throws. He’s thrown multiple interceptions in three of his ten starts. But the Bears view this as just part of the process. A coach can’t instill confidence into a quarterback without allowing room for risk, and subsequently, errors.

So what’s next in the plan? Nagy says the next step isn’t to reign in his second-year signal caller, it’s to improve his ability to recognize and read defenses quickly. That will help him get from that first read to where he must go afterward. Ragone suggests the mistakes Trubisky has made this year have been more about eye discipline than anything else, whether it’s seeing something late or not having his timing quite right with his eyes and feet.

“Knowing when it’s not there and then what is your next reactionary decision. Is it dropping it down? Is it moving to find your secondary target? I think those are the steps,” Ragone says.

“Because I think it’s harder to instill the ‘take the ball down the field’ mentality to ‘Hey just take the underneath throws all the time,’” he continues. “I think we’ve gotten there with him with the mentality of we’re looking to be aggressive. When it’s not there, obviously you need to pull back the reins.”

Adapting to his skills aids in that evolution. Around the league, teams are borrowing from college coaches, biting off chunks here and there for their own purposes. Mercifully, the days of drafting a quarterback to run a specific system without consideration for his skills look numbered. Teams are allowing their players to come in right away and sling it by running offenses tailored to them. In fact, rookies Josh Allen, Sam Darnold and Baker Mayfield are all near the top of the league in average intended air yards, as are second-year stars Deshaun Watson and Mahomes, along with Trubisky. The reason should be obvious: give quarterbacks concepts they know and like, and they’re much more likely to succeed.

“At the end of the day if the player has a familiarity of years of equity built into a play, or a concept, or a way that he’s run something, why not build on that?” Ragone says.

It’s football’s version of not trying to fit a square peg into a round, pro-style offense. And not making that mistake has been key for the Bears this season, according to offensive coordinator Mark Helfrich.

“I think [it has helped] a lot,” Helfrich says. “You have to play to your quarterback’s strengths. Unless you’re turning around handing the ball to your tailback 38 times … you have to play through the quarterback. That’s job one.”

Helfrich spent his entire career in college before coming to Chicago, including time at Oregon with Chip Kelly, to whom Reid credits for shaking up his way of thinking about offense. Helfrich believes this burgeoning adaptation of college concepts into NFL offenses has benefitted Trubisky a great deal.

It may seem intuitive, but it wasn’t that long ago Goff looked totally lost in an archaic offense being asked to do things he wasn’t comfortable doing. And of course, there’s Trubisky himself, a timid, conservative quarterback a year ago transformed into one of the NFL’s most aggressive downfield throwers.

“I don’t know what it was last year and frankly don’t really care in terms of turning the page,” Helfrich explains.

“And there’s some weapons outside that we’ve added that have made life a little bit easier in that regard for him for him. I think a lot of times it’s flipping the switch of ‘Hey we want chunk plays. We want aggressive, smart decisions,’ but aggressive and always err on the side of the desire to make a play rather than let’s not do A, B, or C.”

The commitment to this ideal must be institutional, starting with the head coach. Be aggressive and be communicative.

“As a coach, what you want to do is you want your quarterback to feel comfortable in what you’re doing,” Nagys says. “So, if there’s some plays that doesn’t necessarily fit what he does best, then you want to move on from them. If there’s some stuff that you don’t have that he does well, then let’s look at it and see how it fits what we do.”

Don’t underestimate the value of Nagy’s last point. Coaches, perhaps more than ever, show a willingness to borrow and steal from one another. Helfrich echoed this notion, pointing out the staff makes an effort to watch other teams, borrow plays and concepts to be what he calls “strategically unique.” Finding plays that make it easier to score or convert a third down should be every coach’s goal, ego be damned. Just because it’s not their play doesn’t mean it’s not a good one.

The scary part for the rest of the NFC is this is just the beginning. Nagy said early in the season he was still trying to figure out what he could call and when, not just to see what Trubisky could handle, but because the offense was new for everyone. Helfrich says they’re beyond learning what Trubisky likes, but they’re still working to understand exactly how he sees the game so they can call and design plays based on the way their quarterback thinks about the game.

For Ragone that means making sure Trubisky stays true to himself. He insists the quarterback we saw last year was antithetical to the kind of player Trubisky wants to be. This year has been about reminding him to have confidence in himself and play the way he wants.

“He’s growing into the quarterback that we want him to be, but [also] what he wants to be. Because at the end of the day he has to feel comfortable playing his own skin. That’s the thing about playing this position, you can’t be another quarterback in this league. When you try to emulate someone else, typically you fall because you don’t have anything to rely back on. When you try to be who you really are and you understand that, the strengths and the weaknesses of that person, those to me are when those quarterbacks become great quarterbacks.”

From that perspective, the prudent course with Trubisky may be to treat his rookie season much the same way we treat Goff’s. It doesn’t count. In 2018, he’s shown major strides in accuracy, confidence, and playmaking. His inaccuracy and propensity to hit the wrong color jersey lurks as a potential bug-a-boo, and Trubisky doesn’t want to ride the same line of aggressiveness from his predecessor Jay Cutler.

He’s shown this season, when he sees the game clearly, he can light up opposing defenses. As his playmakers grow -- nascent stars like Miller and Tarik Cohen -- so too will Trubisky. The Bears have instilled the confidence in Trubisky to play the way he wants to play, to push the ball down the field and not worry about mistakes in the hopes he’ll learn from those errors and start making fewer of them.

Their template for getting him there? Let Mitch be Mitch.