Bears need to find out exactly what they’ve got in Mitch Trubisky

It was just one preseason game. It was with reserves and against reserves. But there’s one facet of Mitch Trubisky’s impressive debut that Bears coach John Fox and general manager Ryan Pace can’t ignore: Trubisky turned it up when the lights went on.

That’s the kind of quarterback you trade four draft picks to acquire. That’s a small sample of the “it” factor that compelled Pace to roll the dice on a quarterback many others graded as no better a prospect — or a worse one — than Deshaun Watson or Pat Mahomes.

Even factoring in the circumstances, Trubisky was better in a game than he was in training camp — very often the mark of a winner. He was focused, poised, decisive and accurate. He scrambled without panicking. And his teammates seemed to follow his lead. There were no fumbled snaps. No snaps over his head. And only one penalty besides his own delay-of-game infraction.

For a while, everything seemed to be going the Bears’ way once Trubisky stepped onto the field. Even a penalty on wide receiver Deonte Thompson for spinning the ball after a 24-yard pass play on third-and-18 was waved off when officials ruled Thompson was not taunting an opponent. How often does that happen to the Bears?

Bears rookie Mitch Trubisky completed 18-of-25 passes for 166 yards, one touchdown and no interceptions and a 103.1 passer rating against the Broncos on Thursday night at Soldier Field. He also rushed for 38 yards on three scrambles. (Jonathan Daniel/Getty Images)

It’s unlikely that good fortune is part of the Trubisky Effect, but that doesn’t mean there wasn’t such a thing Thursday night. The Bears have had backup quarterbacks play well in the preseason — Connor Shaw threw a touchdown pass in bit parts against the Patriots (126.4 rating) and Chiefs (153.5) last year. Jimmy Clausen threw two touchdown passes — believe it or not — against the Eagles in 2014. Jason Campbell, Dan Lefevour and Caleb Hanie had their moments.

But Trubisky didn’t just play well. He lit a spark. His impact on the offense was palpable. Circumstances played a part, no doubt. Trubisky represents the hope for a better tomorrow; Hanie, Clausen, Shaw et al. were never going to beat out Jay Cutler. But Trubisky’s impact on the game seemed to go beyond the numbers.

Fox likely saw the same game we did. And he knows the effect a quarterback can have on a team. When he named Jake Delhomme over Rodney Peete in Week 2 of the 2003 season in Carolina that ended in a Super Bowl, it was because he couldn’t ignore it.

“It would have been tough not to start him,” Fox said at the time. “It was very evident that he sparked our offense.”

After eight years of the star-crossed Cutler, the Bears could use a quarterback with good karma. At this point of Cutler’s debut season with the Bears in 2009, we were parsing a Cutler quote to bits, raising the first red flag of the Cutler era and forcing an apology after Cutler’s accurate explanation for a pick on a deep ball to Devin Hester (“Devin is more of a go-get-it guy”) turned into dynamite.

What a difference an era makes. Trubisky is the talk of the town after his debut. The Bears never had this kind of buzz after the first preseason game throughout the Cutler era. Social media gets some of the credit for that effect, but not all of it. This town would be buzzing about Trubisky today even if all we had were water coolers, barbershops and party lines.

But that buzz has been doused by a call for Bears fans to slow their roll. Fair enough. It was one preseason game. And it would be premature to write off Mike Glennon after one bad quarter. But even if Trubisky didn’t win the starting job Thursday night, his debut was intriguing enough that Bears need to find out exactly what they have here.

Follow me on Twitter @MarkPotash.

Email: mpotash@suntimes.com

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