Most major questions about the second year of Matt Nagy's Bears offense start with Mitchell Trubisky and end with him.
Can Trubisky make the next step in Year 2 and read defenses presnap to attack them like quarterbacks in the NFL's upper echelon?
It's a mystery, no doubt.
In this offense's 200-level course, as Nagy has called it, there will be more taking advantage of defenses instead of running plays simply as they're called. Trubisky has to be able to make this step, make adjustments on the fly and burn opponents.
However, whether he does it is not the biggest question mark facing the Bears on offense at this time.
Trubisky has already put up a 95.4 quarterback rating and moved the ball in the passing game well enough for the Bears to be 21st in passing. It's not very good, but it's a starting point.
The baseline for any offense is whether you can run the ball. Regardless of passing or trickery or anything else on offense, a team has to be able to run.
In the NFL if you can't pass, you're not going anywhere. However, running is the assumed part of an offense. At the very least, you should have what's needed to run.
The Bears don't even know if they have this.
Earlier this offseason Nagy was discussing his offense's next step, and knew the emphasis being placed on the passing game.
"And then you look at the passing game," Nagy said. "We were actually better in the run game than the pass game so we'll put it all together. That's the fun and the challenge as a coach."
The trouble with this is the entire passing game is going into it's second year. There should be an advanced level for the starting point. It's the running game that has to prove it hasn't regressed, let alone advance to second year level.
Mitchell Trubisky, the line blocking and the receivers are all in the second year of operating this offense. Bears defensive players, to a man, noted how crisp the passing game looked against them in minicamp and OTAs compared to last year.
There is no reason to think they'll regress from here in Year 2. Even if they stay the same, they've shown they can get by with this.
The running game is entirely a different story.
They're starting the running game with two backs who haven't been in their offense before, two backs who haven't really been NFL starters. Mike Davis started nine games in four seasons with the 49ers and Seahawks. Last year he had 112 carries, the first time he ever went over 68 carries in a season.
David Montgomery is a rookie, and one whose breakaway speed became a question after the combine.
Tarik Cohen is only a change-of-pace back, the guy whose role is running outside on occasion but mainly getting open for catch and run in the passing game. He is not the starter. The Bears feature inside zone as the basis of their running game and they're never going to have a running game like this with Cohen consistently running between tackles.
When the Bears had Jordan Howard, they knew they had a back who could at the very least handle the workload and had done it in the past without turning the ball over. He had only five fumbles in 778 career rushes. He wasn't going to help in the passing game or be a consistent breakaway threat as a runner. Despite his warts, they knew what they had.
There is every indication these two backs should at least be able to avoid the turnovers. Davis has only one fumble in 234 career rushes and Montgomery averaged only one per year in college.
Yet, it's a risk they've chosen to take and it's an uncertainty. It's unknown whether either back will be able to run the ball and be consistently successful with 175 to 225 carries in their first NFL attempts at doing this.
The Bears believe or suspect they will. Then again, the Bears in the 1990s thought they had something when they drafted Curtis Enis and Rashaan Salaam in the first round and look what they got. Houston took D'Onta Foreman in the third round in 2017 and Seattle C.J. Prosise in the third round in 2016 and you haven't seen their photos on a Wheaties box yet.
Until the trust in their running backs is verified, they remain a question. The OTAs and minicamp show almost nothing for backs since there is no contact involved.
Already the Bears know baseline for the passing game and Mitchell Trubisky. It was what they saw last year.
These running backs start out this season in a 200 level course without even taking the 100 level.
Whether they can handle it is a real question.