BOURBONNAIS — Before he came to the Bears, Khalil Mack was known mostly superficially in Chicago — a dominant player seen through highlights, an occasional televised game and a résumé that included four Pro Bowl selections and the 2016 AP Defensive Player of the Year Award.

As it turns out, he was much more than even that impressive standing with those lofty credentials. Mack’s presence invigorated the entire team from the moment he arrived, and his work ethic raised the bar for the Bears’ defense. Like Julius Peppers — known as a sack specialist who took plays off — and Marian Hossa — known mostly as a goal-scorer — Mack, 28, is a superstar acquisition whose overall game exceeds his reputation. His impact has been exponential.

And the more we get to know him, the better Mack’s story gets. In his first training camp with the Bears, when he could be coasting at least a little bit to save his A game for the regular season, Mack has been a freight train going full speed ahead. And he’s proving to be a practice-wrecker as much as he is a game-wrecker.

“It’s real, it’s completely real, and it’s just him,” outside linebackers coach Ted Monachino said. “It’s the character of the man. It’s the focus and it’s the love of his teammates. I’m not trying to baby him. He doesn’t want that. He wants every rep he’s supposed to get, so he can work on his craft every snap possible.”

Mack proved last year that he doesn’t need training camp to play at an All-Pro level. But he is intent on making the most of camp and building chemistry with teammates who still are relatively new to him.

“Oh, man, it’s fun,” he said. “You have the [defensive backs], the linebackers, the D-line — everything is effort. You can give what you can give, and they go out and do their job. But everybody is making plays.”

It’s only training camp, but after seeing the Bears’ defense winning the battle daily in practice, the offseason trepidation over the impact of Vic Fangio’s departure has given way to visions of dominance in 2019.

“You’ve got to have that cohesiveness,” Mack said. “It’s an energy you feel when you’re out there. You can’t help but bounce around and feel light because everybody is flying around to the ball and wants to make a play.”

Mack couldn’t hide a smile when told that quarterback Mitch Trubisky admitted a bit of frustration at battling the Bears’ energetic defense.

“I didn’t know he said that,” Mack said. “It’s funny, but . . . that’s what you want. You want the quarterback to be frustrated. That’s nice to hear. But he’s doing his thing, and he’s getting better, as well. You can see the growth through him and us, and he’s helping us, as well.”

The regular season will determine what is real. But for now, the Bears are almost giddy with Mack’s impact. Asked simply, What can you say about Khalil Mack? Monachino responded with a hearty laugh.

“Where do I start?” Monachino said. “My job is to not screw him up — give him a few tools that he can add to his toolbox. There are certain situations where he can play better.”

Accomplishing that seems only like a matter of time. This is a self-motivated player in his absolute prime, determined to justify the high price the Bears paid to get him — two-first-round picks and a six-year, $141 million contract.

“Nobody has a higher expectation of how they play than Khalil . . . so every day he goes out to prove it,” Monachino said. “Every day he goes out there to make sure everybody understands he’s worth it. The time and resources this organization put into [him], he’s trying to make sure that all pays dividends for us.”