Soon after that loss, Nagy considered the growth of quarterback Mitchell Trubisky in their first year working together and envisioned what was to come.
"We're lucky to have him," Nagy said then. "I'm looking forward to the future. I really am. Because the city of Chicago is lucky to have that kid at quarterback."
In the aftermath of the loss, Nagy continued to build his plans for the potential he saw in Trubisky's future. Nagy believed that level "202" for Trubisky, as he has termed it, would involve anticipating what a defense would do and beating it over and over again.
That's why Nagy created a game plan for the Bears' opener against the Packers with so much built for Trubisky -- the downfield throws, the timing routes, the run-pass options and all the creativity. So much of what Nagy had planned was based in his belief of Trubisky taking the next big step in his development.
After the game, Trubisky said the constant personnel mix was part of why the offense felt "scattered" -- a word that incidently was an indictment to his capabilities and Nagy's gameplan.
Perhaps Nagy truly felt Trubisky would emerge into the company of 2017 draft classmates Patrick Mahomes and Deshaun Watson. Now that Trubisky is in his third NFL season and second year with this coach, system and supporting cast, Mahomes and the Watson are the standard to which Trubisky should rightfully be held.
And it's why Nagy and the Bears were so distraught after a 10-3 loss to the Packers. Trubisky not only failed to reveal that next step, he appeared to have regressed.
In the week since, the Bears have protected Trubisky closely in a careful effort to preserve his confidence. The team even instructed Trubisky not to discuss that performance during his media session Wednesday.
But how do Nagy and the team truly feel about Trubisky's abilities?
The Bears' game plan against the Broncos on Sunday should say plenty about where Nagy is with Trubisky. If there's a defensive mind capable of confusing Trubisky more than the Packers' Mike Pettine, it's former Bears defensive coordinator Vic Fangio, the Broncos' first-year head coach. Fangio saw the first two years of Trubisky's development in practice and game situations.
When Nagy talks about establishing the Bears' rushing attack more, he knows that may be the team's best chance of leaving Denver with a win. If Trubisky throws 45 times like in the opener, Fangio will find ways to frustrate him.
Nagy now knows better, having seen his plans and hopes for Trubisky already receive a reality check.
The manner in which star receiver Antonio Brown ran himself out of Oakland reminds how fortunate the Bears are with the players in their locker room.
When Nagy said in August that his team has "no turds," he meant it. The Bears take pride in the kind of character they've brought into their locker room. At the other end of the spectrum from Brown is Bears receiver Allen Robinson, whom the team has come to greatly respect in the locker room.
"The way he practices and treats every single play like it's the last play he's ever going to have is just exemplified and magnified to the other players," Nagy said. "He's a multiplier. He makes his teammates around him better.
"That's the complete opposite of distraction. You want more of that."
Can Robinson perform as an elite receiver this season? It's in play. I'm willing to say he will top his career-highs of 80 catches and 1,400 yards.
Despite an uneven performance from Trubisky, he still connected with Robinson seven times for 102 yards against the Packers. Trubisky targeted Robinson 13 times, which he said Wednesday was something he's plenty comfortable doing.
"That was a pretty good number," Trubisky said. "I mean if he's open, throw it to him. Even when he's not, he's open."
Robinson is more comfortable in his second season with the Bears after spending his first coming off a torn ACL and adapting to a new team and offense. Now he appears poised to produce at a high level.
The Bears held future Hall of Fame quarterback Aaron Rodgers and the Packers to only 213 yards of offense and 10 points, but it wasn't enough.
Despite the Bears remaining in the game due to their defense -- and losing because of their sputtering offense -- the words of players like defensive lineman Akiem Hicks resonated this week. The Bears defense took ownership for the opening loss just as much as those on offense.
There's also the belief that this defense is just getting started on something special.
"Our defense is and can be more dominant," Hicks said. "We just got to prove it. We got to prove it."
Broncos star pass rusher Von Miller watched the Bears' loss to the Packers and found himself surprised. He had a similar feeling as Nagy did in watching the film.
"They got way more in them," Miller said of the Bears offense, pointing to the odd game flow that also affected the Packers.
Of course, the Bears will have to contain the Broncos' stars on defense like Miller if they hope to get their offense moving.
It seemed like Rodgers and the Packers were targeting Bears reserve safety Deon Bush on the lone touchdown drive of the opener. Why was he on the field with starter Ha Ha Clinton-Dix healthy?
Because the Bears had planned to play Bush on their third series of that game, defensive coordinator Chuck Pagano said. They will continue to rotate him in moving forward.
"We're going to get that kid some playing time," Pagano said. "He's earned it."
Handling the thin air a mile high in Denver can be challenging, so how will the Bears handle it?
Take it from Bears linebacker Aaron Lynch, who recorded a sack during a game in Denver in 2014.
"I don't think about it," Lynch said. "Live in the same world. I don't think the altitude makes a difference unless you think about it. It's something mentally, you psyche yourself thinking about it too much during the week, you're going to notice it. But if you just go into the week like you're going to play in California, I don't think you're going to notice the difference."
"We're moving on." -- Trubisky, Nagy, quarterbacks coach Dave Ragone and others
TE Trey Burton (groin) -- For the first time since suffering his most recent groin injury, Burton spoke to reporters Thursday and expressed his frustration over the situation. The Bears are remaining optimistic that Burton can play, but he likely will be a game-time decision once again. Even if Burton is active, he shouldn't be expected to play much of a role.
DL Eddie Goldman (oblique) -- Goldman suffered an oblique issue during practice Wednesday and was held out a day later. This is a major concern for the Bears, who have come to appreciate the presence of their big nose tackle. Goldman's ability to gain leverage in the trenches would be greatly affected if the oblique injury lingers.
At mile-high altitude, I expect a low-scoring game. The Bears will break through with a pair of touchdowns on offense and take this one over Vic Fangio and the Broncos.