The Steelers' passing offense hasn't taken any steps forward from last year under Matt Canada.
After nine games the Steelers average 236.1 passing yards per game, short of the 250.2 passing yards per game they averaged under Randy Fichtner last season. Ben Roethlisberger averages 1.25 passing touchdowns per game compared to the 2.2 passing touchdowns per game he averaged last season.
Canada hasn't been able to unlock the passing offense as his unit adjusts to his rhythm of play calling, a new, young offensive line, a feature running back in Najee Harris, and Roethlisberger trying to find his feet in the middle of all those new elements.
It's been a consistent struggle for Roethlisberger to find his rhythm in Canada's offense, even if some of the problems revolve around him reading and reacting the wrong ways to opposing defenses. But in all of Roethlisberger's games he's yet to make use of deeper passes down the middle of the field. Out of Roethlisberger's 196 completions on 299 passes for 1,986 yards, ten touchdowns and interceptions, Roethlisberger has only attempted 25 passes over ten yards down the middle, completing 12 of them for 242 yards and a touchdown.
Canada has drawn up plays with receiving options in those parts of the field for Roethlisberger, but it hasn't manifested into any significant production. When Mason Rudolph made his first start of the season, it was a chance to see if another quarterback would attack that part of the field.
That didn't happen Sunday:

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Rudolph only completed one of three passes between the numbers that was caught beyond 10 yards of the line of scrimmage. That continues the trend that shows Canada is counting on the Steelers' underneath passing game to accomplish the bulk of what his offensive schematics create for his quarterbacks.
Some of that can make things easier for quarterbacks to complete less risky passes and give chances for playmakers to make defenders miss and create bigger plays on their own. But for that to happen, the proper mismatches have to be created, and the Steelers have to show the threat of being able to hurt defenses with passes beyond the line to gain to open up more short passing opportunities.
Canada does have plays that challenge defenses vertically and stress matchups for defenses to consider who deserves the most coverage. That was part of the product of the Steelers' only touchdown against the Lions, when James Washington caught a wide open touchdown while five Lions defensive backs focused on Diontae Johnson:
Teams are starting to pick up who the top targets are for the Steelers in key situations. That means players like Johnson with three receiving touchdowns and Pat Freiermuth with four receiving touchdowns will get highlighted by defenses.
That's when it's smart to play off defenses' tendencies in those situations. But that doesn't mean it's as simple checking it down to other receiving options to solve those issues. Canada and the Steelers have to scheme up chances opportunities for those receivers to win in favorable spots.
That's not what happened when RayRay McCloud was targeted with a pass to the flat where he caught it one yard beyond the line of scrimmage on a 3rd and 6 situation. The Lions were ready, and he was unable to make his man miss in space:
If the Steelers are going to win a one-on-one situation in that kind of space, that's a prime opportunity for Harris, who's forced 33 missed tackles according to Pro Football Focus, fourth-most of any running back in the NFL.
But when you look back at the play, it's obvious there were other options, like Johnson who ran beyond the sticks and had a step on his man. That's where it goes back to question of whether it's on Rudolph or Roethlisberger for committing too quickly on an underneath read, or if that's the pre-determined read required because of play design.
We know both Mike Tomlin and Canada have commented in the past about how when Roethlisberger targeted Harris on an underneath pass against the Bengals on fourth down in the red zone when there were multiple receiving targets available in the end zone. So that suggests that it's up to the quarterbacks to make the proper reads.
That's where Canada may be asking a lot of Rudolph, as he's forced to make several quicker passing decisions that stress detailed processing of defenses and proper reactions to those reads. Rudolph has been a quarterback who's depended on his pre-snap reads for success since his days at Oklahoma State, which means if he's fooled by a defense's alignment, he's a lot less likely to adjust while a play unfolds.
Watch this failure to convert on third down when Rudolph again committed too early to his target, hitting Freiermuth in the right flat where more defenders were for the Lions. If you look to the opposite side of the field, Harris ran a similar route with only one defender to beat:
Not that this was a terrible read by Rudolph, but it's a situation where Harris most likely would've stood a better chance to score with a single defender in front of him than where Freiermuth was up against multiple defenders and required two blockers in front of him to succeed.
But again, it's about finding the right matchups.
Canada does draw up plays where defenders have to make tough decisions that can open up opportunities. Watch this missed throw from Rudolph, who missed McCloud in the end zone. Freiermuth was lined up inside of McCloud and drew a double-team that opened up space for McCloud to be open, but Rudolph missed when McCloud broke towards the end zone:
It's a miss from short distance, but it was also one of 50 passes Rudolph threw during the game.
Short passing concepts require quarterbacks to be more consistent in their timing and their processing of defenses several times in a game than an offense that might have Rudolph throw less times, but for bigger chunk plays.
The point of shorter passes is to create easier opportunities for the quarterback to get the ball in the hands of his playmakers so they can create yards after the catch. But if teams are so geared up to defend the short passing game, that objective becomes a lot more difficult. And for backup quarterbacks like Rudolph, it asks a lot to consistently beat.
That's where Canada and the Steelers have to simplify things for Rudolph. It's good to have more concepts that play off the run to create simpler reads on the offense further down the field. That way the sample size for Rudolph isn't as large, and it can still create one-on-one opportunities for him to target.
Canada did this on occasion against the Lions, like this 17-yard completion to McCloud off play action. McCloud runs a deep crossing pattern behind the Lions' linebackers who are biting closer to the line, thinking that Harris is about to run. Once McCloud got in space, Rudolph just knew he had to lead him:
Even if Roethlisberger returns from the Steelers' COVID-19 list before Sunday night, Canada needs to find more ways to mix up the passing game so that opponents can't so easily key in on underneath passes.
If Canada wants the passing game to open up more, he's going to have to find more consistent ways to make sure the Steelers' best playmakers with the ball in their hands are getting favorable matchups to make one man miss on the passes short of the line to gain. Then, Canada also has to find better ways to simplify the intermediate-deep passing concepts to get Roethlisberger and Rudolph to have higher percentage chances on those throws.
Fortunately, defenses do appear to show a lot of respect to Harris when he's on the field. Using that respect to create the other passing opportunities might be the key.