SOLDIER FIELD — It was just a preseason game. He was facing backups. The other team wasn’t scheming against him.

The reasons to dismiss Mitch Trubisky’s performance Thursday night are out there. And they’re fair. But it would be foolish not to be encouraged by the No. 2 overall pick’s debut in a Bears uniform, because the raw talent Trubisky showed in college was on display on an NFL field Thursday night — and that matters.

“Obviously you can see why he was picked in the draft where he was,” head coach John Fox said. “I think that was evident.”

Of course, the raw talent isn’t in question with Trubisky. It never has been. But like we learned during the Jay Cutler era, it’s what you do with that talent that matters. And the key question with Trubisky going into the draft was: Is a 13-game college sample enough to prove that he can execute at the NFL level?

Consider Thursday night’s performance Game 14. It wasn’t a regular season game, so you can’t put Trubisky in Canton just yet. But it was a step up in competition.

“(The game) seemed faster. Pretty close to practice, except you have guys trying to take your head off,” Trubisky said. “It was good. I just tried to take a deep breath, show command and poise in the huddle and at the line of scrimmage, see the defenses and really just do my job.”

And the rookie passed the test with flying colors. What you saw was almost a carbon copy of Trubisky’s college tape. He was poised in the pocket, felt the pressure when it came, and used his feet to step up and avoid it. He was accurate with a strong arm and quick release, while showing off the athleticism he didn’t get enough credit for going into the draft.

“Yeah man, who wants to get tackled? Who wanted to get sacked? Not me,” Trubisky said. “No negative plays, right? So yeah, I’m going to take off.”

Perhaps the most impressive part of Trubisky’s game was what he did in-between plays, running the offense so smoothly. That hasn’t always been the case in Bourbonnais and his only obvious blunder Thursday night came when he took a delay game on 3rd-and-2 at the 2-yard-line.

“It helped having a play sheet,” Trubisky said. “It’s not the extent of a normal game week, but we did prep for this game a little bit. And it’s a little different from practice, where you don’t exactly know the calls every day unless we get the sheet.”

Give offensive coordinator Dowell Loggains credit. He has tested Trubisky hard in practice, keeping the rookie on his toes, which made it easier on him Thursday night when he had a script.

But that’s where everybody needs to be careful and remind themselves that this is the preseason. Yes, offenses always go into regular season games with scripts they can study ahead of time, but opposing defenses spend an entire week game-planning, which frequently forces offensive coordinators to ditch those scripts by the end of the first quarter and adjust. Teams do little to no game-planning before the first preseason game. While the Broncos’ defense is talented, new defensive coordinator Joe Woods wasn’t exactly disguising coverages and throwing exotic blitzes at Trubisky.

In other words, that was probably the easiest test the rookie will face in the NFL, and it matters because Trubisky’s struggles at North Carolina came against defenses that were good at disguising coverages. He’s going to be tested at a much higher level going forward.

That said, it would be silly to discount Thursday night’s performance. Trubisky still completed 18-of-25 passes for 166 yards and a touchdown with no interceptions. And he nearly had three touchdowns, given that Rueben Randle was stopped at the half-yard-line and tight end Dan Brown dropped a catchable (but low) pass in the end zone.

Fox was quick to point out that “it was one preseason game,” and he refused to open up a real quarterback competition between Trubisky and starter Mike Glennon.

And Fox is right. It was just a preseason game. But it was also Game 14 in the Trubisky evaluation process. And it was more evidence that he can be a very good NFL quarterback.

Adam Hoge covers the Chicago Bears for WGN Radio and WGNRadio.com. He also co-hosts The Beat, weekends on 720 WGN. Follow him on Twitter at @AdamHoge.