Replacing Lovie Smith was a tough choice, one which looked like a defining moment in GM Phil Emery's tenure. However, who he chose to replace Smith will leave a bigger mark on his time as Bears GM.
As Sun-Times contributor Matt Schwerha said on Twitter this morning, the moral of the story is, never doubt Jimmy Johnson.
A week ago, Johnson came out and essentially said (in so many words) that Trestman was going to coach the Bears. Now, I said to hold on before we got excited (or depressed, take your pick), as it seemed more than premature given the Bears hadn't even reported narrowing down the field yet.
We knew Trestman was in the hunt, but how much toward the front was unknown.
Turns out, Johnson was (more) right and everyone else was (more) wrong.
Who the finalists were, whether Mike McCoy or anyone else was ever in serious consideration is hard to say.
So let's focus on the two things we can talk about, because not only is Trestman the new head coach, but the Bears have hired former New Orleans Saints interim coach Aaron Kromer for the offensive coordinator and offensive line coaching job.
He wanted to have options—as long as those options fell outside the "same old, same old" names that are trotted out every year.
This is the defining moment for his tenure. If this works, he'll look like a genius. If it implodes, he might have a short-lived career as the team's GM.
Emery was very smart, though, and he chose coaches with plenty of appeal beyond the upside of "something new."
Both coaches are well known as people whom players and staff respect, and both bring impressive resumes to the table.
Trestman oversaw offenses that led to an AFC Championship Game (with the Cleveland Browns in 1989) and a Super Bowl appearance (with the Oakland Raiders in 2002), capping a season in which his offense was first in the NFL and propelled Rich Gannon to NFL MVP.
That's not to say he'll wave some sort of magic wand and fix it—just that he has been successful doing it before.
On top of that, these two worked together for the Raiders in 2001 and 2002, so they have a familiarity with each other already.
The thought process is, Trestman will call the plays while Kromer will work on the offensive line and to some extent the running backs as well as help design the offense.
Emery also brought in a coach who appears to be content to leave the bulk of the defensive staff—and scheme—alone.
As I said before, if it ain't broke, don't fix it. It's aging, but the defensive scheme and even the aging players remain very viable.
Trestman (and by extension Emery) is wise enough to leave it alone—they'll get youth through the draft but not force a complete changeover.
That's just smart, considering how much is riding on the changes to the offensive side.
Trestman has shown that he can take a decent quarterback to an elite level (Rich Gannon was never as good as he was with Trestman either before or after), and Kromer has put together some very solid offensive lines.
These are the two most vital pieces to this offense and the ones that most need addressing.
Emery has bet on two coaches who lack specific experience in the NFL for their roles but overall have plenty of knowledge and expertise at a pro level and can specifically attack the problems in the offense.
It really is an "all-in" move.
If he's right, he's going to look like a genius.
If he's wrong, he might not just get fired—Chicago fans might chase him out of town with torches and pitchforks.
Check out the B/R NFC North Facebook page. Like us and keep up with everything NFC North on Bleacher Report.
Follow me on Twitter at @andrew_garda.