BOURBONNAIS, Ill. — Mitch Trubisky completed his 12th practice of training camp on Sunday, and it was one of the best practices — if not the best — he’s had down at Olivet Nazarene University. He was accurate and anticipated where his receivers would be, no matter how tight the window.

Those throws impressed coach Matt Nagy, but from a larger view, the growth Trubisky has made from Day 1 of training camp has been noticeable for fellow quarterback Tyler Bray.

“It’s night and day,” Bray said of Trubisky’s understanding of Nagy’s offense. “It gets thrown at you pretty fast. At first, your head is kind of spinning. You don’t know what to think. Then after a while, it kind of settles down and it becomes a lot easier.”

Bray spent the last four years working, largely behind the scenes (he only appeared in one regular season game), with Nagy in Kansas City and knows the offense well. That was why the Bears brought him in as a third-stringer behind Trubisky and Chase Daniel, the latter of whom has a strong understanding of Nagy’s offense, too.

While the 2017 No. 2 overall pick has yet to operate Nagy’s offense in a game — he’ll probably do so for a series or two against the Cincinnati Bengals on Thursday — what’s worth noting is Bray believes Trubisky has had enough reps running the offense in training camp to have a good grasp of it. That’s shown up not only on the field, but in film sessions and meeting rooms, too.

“It’s just more and more reps,” Bray said. “The more reps you get at a play, the better it’s going to be. And so he’s had a enough reps under his belt for pretty much every play and so you can see out there, his reactions to everything is a lot better.”

The goal of training camp, especially the first few weeks of it, for Nagy and offensive coordinator Mark Helfrich was to throw a bunch at Trubisky to see what he understands and what he’s able to effectively operate. As Nagy and Helfrich slowly introduce gameplanning to practices leading up to the third (or, for the Bears, fourth) preseason game against the Kansas City Chiefs Aug. 25, the offense will be pared down a bit and become more tailored to what Trubisky’s shown he can do.

But from Bray’s point of view, the answer to the question of “what can Trubisky do?” is, well, everything.

“He’s big, he’s fast, he’s got a really strong arm,” Bray said. “I mean, the guy can throw it, run it, pretty much do whatever you need him to do.”