Chicago Bears quarterback Mitch Trubisky (10) is sacked on third down during the second half against the Green Bay Packers at Soldier Field in Chicago on Thursday, Sept. 5, 2019. The Packers won, 10-3. (Armando L. Sanchez/Chicago Tribune/TNS)

CHICAGO - An odd vibe smothered Soldier Field late Thursday. In the fourth quarter of a huge game on a big stage, the Bears were driving. They were entering the red zone and knocking on the door of a potential tying touchdown.

It was the type of scenario championship teams live for, a moment confident crowds help fuel. Yet the energy across the lakefront was eerily muted.

Where there once had been deafening excitement, there now was just contagious apprehension. A game that had begun with Super Bowl hype, a season that launched carrying Super Bowl hopes, suddenly had way more anxiety than Chicago was prepared for.

First-and-10 at the Packers 16.

Opportunity.

Somehow, though, a once-amped crowd had been so disheartened over the previous 2 1/2 hours that it felt like a fait accompli. The Packers' seven-point lead felt like 40. The next disaster seemed inevitable.

Naturally, on third down from the 16, Mitch Trubisky stared right at Allen Robinson from the snap, allowed safety Adrian Amos to break on the corner route and threw a loss-sealing interception in the end zone.

The reaction proved apropos. Between the flustered boos, the distressed looks and the agitated disbelief, it felt like footage from the grounds of Fyre Festival.

Bears fans had signed up for an unforgettable and exhilarating experience. Alas - on the first night of the season, anyway - not only would there be no Major Lazer, no Instagram models, no party that was absolutely lit, there wasn't even running water or electricity.

Looking for the VIP luxury villas? Sorry, all that's available are rain-soaked beds in disaster relief tents.

That premium gourmet food everyone was expecting? Here's your cheese sandwich.

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OK, so perhaps an important lesson was folded into Thursday's demoralizing loss. The 2019 season, Bears fans were reminded, will not be easy for those with weak stomachs. It also might be hazardous for those who struggle to think critically, those who want their hearts to forecast the future rather than relying on sound and reasoned judgment.

Because, let's be honest, for those who wanted to listen, there were warning signs throughout August that Trubisky and the offense weren't going to instantly transform into the 2007 Patriots. This always was going to be a team with an elite defense waiting to see how long the work-in-progress offense would need to pick up some slack.

Offensively, it had become apparent this was going to be a bit of a roller coaster, particularly in the first month or so.

These are the things that can be detected over four weeks of training camp practices when there are too many days without much offensive rhythm; too many moments when a young quarterback appears to be scuffling; too many throws that land in the hands of defenders.

The idea of Trubisky becoming a true MVP candidate in 2019 was always fanciful, a premise based mostly on blind loyalty and promoted in pockets of the super-fan blogosphere. But promises of a major Trubisky breakthrough were also occasionally pushed by some in the media world who gleefully guzzled the Kool-Aid without reading the ingredients label.

Let's not forget that Trubisky arrived in Bourbonnais and firmly asserted before the first day of practice that ball security was among his top priorities for camp, that he didn't need the same leeway as he had in 2018 to make mistakes and test things.

"Taking care of the football," Trubisky said, "will be more of an emphasis this camp."

Yet when the interceptions kept coming throughout the Bears' stay at Olivet Nazarene University, Trubisky's most loyal defenders found the bargain bin of fallback reasons.

The Bears' elite defense, after all, was aggressive and sharp and full of playmakers. Who was to say a young Peyton Manning wouldn't have been throwing all those picks too?

And isn't summer practice the trial-and-error lab where mistakes are not only insignificant but encouraged?

By Week 1, the reasoning went, the Bears will have their core concepts and bread-and-butter plays identified and be totally ready for action. Packers, beware.

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To be perfectly fair, there was little pointing toward a total meltdown by the Bears offense on the big stage of the NFL's season opener. And we may get to January and look back at Thursday's implosion as far and away the ugliest offensive showing of the season. (For the Bears' sake, and for Trubisky's sake, that better be the case.)

But the Bears coaching staff, and by extension the fan base, better adjust the immediate expectations for what their starting quarterback is capable of producing on a consistent basis. The Bears can still charge into the postseason and deep into January with this ridiculous defense and a sturdy running game that helps the offense become average or slightly above.

Meanwhile, Trubisky is talented enough and surrounded by enough talent in the huddle and in his meeting rooms to produce a handful of dazzling performances - maybe even one or two before the mid-October bye week.

Yet until further notice, it remains reasonable to trust the Trubisky assessments from those not intoxicated by Chicago's grand hopes. Hall of Fame quarterback Steve Young, for example, saw Trubisky with a chance to rescue his team in the fourth quarter of a big game last week. And then Young saw the 25-year-old quarterback throw that inexcusable pick.

"I want him to grow and start to be the reason why the Bears win," Young said on ESPN after the game. "And what I mean by that is when they win a football game, you say: 'Well, that's Mitch Trubisky. He did that.' And that's the place he needs to get.

"Yet when the game's on the line, when he can try to go win the game, he does a high school staredown and the safety moves over and he throws it right to him. Honestly, that's criminal at this level."

NFL Network analyst David Carr reviewed Trubisky's season-opening struggles and was bothered that he was so frequently locked in on his first read and nothing else.

"And when it wasn't there," Carr said, "he panicked a little bit. ... You're going to have your first read covered up a lot of times in this league. You've got to be able to work through your progressions. That's a little concerning."

Packers cornerback Tramon Williams may have had the most damning criticism of Trubisky, offering a glimpse into the mindset of a defense that shut him down.

"We wanted to make Mitch play quarterback," Williams said. "We knew they had a lot of weapons. We knew they were dangerous. We knew all of those things. But we knew if we could make Mitch play quarterback, that we'd have a chance."

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For the short term, Trubisky and the Bears will have to wade through the Week 2 pile-on and work to change minds. That's the nature of this beast. And one abysmal performance to open the season shouldn't be enough to send Bears fans jumping off a bridge.

In the coming weeks, an encouraging performance or two from Trubisky and the offense will come and steady the discussion. That's both obvious and necessary.

But it's also important to recognize what Trubisky's profile is and has been around the league for some time now. Earlier this summer, veteran NFL reporter Mike Sando of The Athletic surveyed 55 coaches and executives to get a sense of which tier every starting quarterback belonged on.

Trubisky, per Sando's appraisal, landed in Tier 3, lumped in with Kirk Cousins, Dak Prescott, Jimmy Garoppolo, Derek Carr, Andy Dalton and Marcus Mariota.

To reiterate, this wasn't one reporter's cockamamie no-homework-required ranking system. This was a snapshot of what the rest of the NFL currently thinks of Trubisky.

And after Thursday's clunker against the Packers, those who need to see Trubisky's breakthrough to believe it were nodding.

There are still worries Trubisky hasn't shown the processing ability to be a surgeon from the pocket.

There is concern his confidence must be managed carefully on a weekly basis.

There are fears Trubisky ultimately might be a win-with guy more than a win-because-of standout.

With all of that comes the reminder that becoming an elite, championship-level, MVP-caliber quarterback - joining the ranks of Drew Brees and Tom Brady, Aaron Rodgers and Ben Roethlisberger - has a mind-bending degree of difficulty.

And the odds against Trubisky reaching those heights remain astronomical. Just ask Carr. Or Dalton. Or Mariota. Or fellow Tier 3 quarterback Jameis Winston.

This isn't negativity. These aren't scare tactics. This isn't some fatalistic overreaction based on one night's ineptitude. It's simply a caution that a Bears team with a truly special defense might have to proceed with a middle-of-the-road quarterback while this window to win the Super Bowl is pried open.

Every die-hard believer and doubting detractor can process that however they wish. Just be aware of the risk involved in offering that deposit for a once-in-a-lifetime thrill ride in the Bahamas.

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