Carter's Classroom: Where it's safe to trust Trubisky

The Steelers signing of Mitch Trubisky brings a new face to the quarterback room in Pittsburgh. But nobody will care if that face doesn't come with an arm that can sling passes more than 15 yards downfield, legs that can extend plays when pressure breaks through the offensive line, and the football IQ to take advantage of defensive mistakes for big plays.

Trubisky doesn't put all of that into a single package that will resurrect the Steelers' offense to greatness, but he does have the tools of a 27-year-old quarterback who can do things Ben Roethlisberger couldn't at age 39 last year. What Mike Tomlin, Matt Canada and quarterbacks coach Mike Sullivan have to do is craft a plan for Trubisky's skillset to make big throws and scrambles in games, while not asking too much from him as a playmaker or a field general. That can be tricky, but the writing is on the wall, and in his tape from the past five years.

Trubisky skyrocketed up big boards for the 2017 NFL Draft to be the second overall pick by the Bears, who traded up to get him over Deshaun Watson and Patrick Mahomes. He did that by not starting until his senior year at North Carolina when he threw 41 touchdown passes, just shy of Kenny Pickett's now-ACC record 42 touchdown passes in 2021, and showing off a strong arm with decent mobility to scramble for yards and buy time to throw on the run.

But the Trubisky we now know doesn't have the same shine with a 29-21 record as a starter in the NFL with 64 touchdown passes to 38 interceptions with a lifetime passer rating of 87.2, a rating that would tie Jalen Hurts' passer rating for the 2021 season. Instead of being the Bears' franchise quarterback for the next decade he spent last year backing up Josh Allen, and he now gets a second chance to show he can lead an offense.

The Steelers don't need Trubisky to be an All-Pro quarterback, just one who can make the throws presented when schemes align and can take advantage of his targets winning in single coverage or finding the soft spot of zones. That especially applies to being able to throw the ball downfield, where the Steelers didn't get much production out of Roethlisberger in 2021. The now-retired quarterback completed only 29.6 percent of his deep passes (20 or more air yards) in 2021, the worst such percentage in his career since 2012. 

After Trubisky's rough introduction into the NFL with a 4-8 record and completing only 33.3 percent on deep passes, he improved that number over his next two seasons as a starter by completing 37.8 percent in 2018 and 34.4 percent in 2019. For a comparison, Roethlisberger hadn't completed a higher rate of deep passes since his 36.4 percent in 2016 and 38.3 percent in 2015. 

But Roethlisberger's limited deep ball ability in 2021 means Trubisky's talents are a welcomed boost in Canada's offense. Here's one example of the raw skill Trubisky can bring in 2022 from his 2018 tape. Notice how the pocket started to break down against Washington and he needed to buy time by rolling to his right. When he does, he notices Washington doesn't have a deep safety in front of Anthony Miller and lets a good ball fly down the sideline for a 36-yard touchdown. It was initially ruled incomplete, but upon review was awarded to the Bears:

When Trubisky locked in on his guy, he could hit the occasional deep ball that threatens defenses who might try to load the box or leave receivers single covered down the sidelines. 

Teams allowed that a lot against the Steelers in 2021 because they weren't worried about Roethlisberger's deep-ball ability. That allowed defenses to focus on stopping Najee Harris in the run or the various short passing concepts Canada drew up for Roethlisberger. Forcing defenses to honor more of those deep shots will open up more opportunities for those aspects of the offense while still allowing for more deep passing touchdowns.

But make no mistake, Trubisky has plenty of flaws, especially when it comes to consistency. You can feel good watching a lot of his highlights, but he has plenty of lowlights as well. There's plenty of his passes that missed their targets for one reason or another when they were properly schemed up. Watch this simple out route he missed on a third-and-long against the Saints in 2019. The coverage scheme appears to be cover 3 and that gives Trubisky an open sideline, but he misses wide of his man:

Like I said, consistency will be part of the questions Trubisky has to answer.

He's worked to improve there, and his 67 percent completion rate in 2020 was the best of his career, ranking 12th among quarterbacks that season. But maybe more important than questions about accuracy are the questions about his ability to read the field. When you watch him play, Trubisky looks like he's at his best when he's identified his primary read against a defense and knows when to switch to his second and sometimes third options.

But those progressions aren't something he's mastered, which is why he didn't catch on as a long-term quarterback with the Bears. When watching most of his interceptions, you can see Trubisky commit to a concept or a target without any regard for the defense he's facing on a given play. Sometimes that's fine when given real one-on-one chances with a receiver, but in the NFL, teams will disguise looks to draw interception chances with double and triple coverage.

Take this interception from 2019 as an example, when the Packers' safeties showed cover 2 with their alignment at the pre-snap. When the ball was snapped, Miller's deep post pattern looked like it might split the safeties. But the Packers showed they were in a cover 3, and three defenders drifted with Miller for the play. Trubisky stuck with his initial read instead of switching off to see Allen Robinson, the team's best receiver, in a one-on-one chance while running an in route that could've gone for a big play:

It's these mistakes that the Steelers coaching staff have to limit from Trubisky.

How to do that will definitely involve game planning and further roster building so that the Steelers are counting on their defense and run game to step up more often than Trubisky. Throughout 2021 and through most of the 2019 season with Mason Rudolph and Devlin Hodges, Tomlin would handle questions about third-and-long failures by saying the problem was that they were in the situation in the first place, rather than any opportunities missed on that given play.

Steelers fans might be used to Roethlisberger slinging bombs around the field to wipe out bad down-and-distance situations and flip field positions from his glory years. But what made Roethlisberger a great quarterback in his best years was knowing when to take those shots more often than not, and having the ability to fit the ball into tight windows when making those plays.

Trubisky isn't what Roethlisberger was to the Steelers during his best years. While Tomlin and Canada can draw up game plans that include more deep passes because of Trubisky's young arm, they also have to limit the times in which the team's hopes hang on needing Trubisky to succeed in such situations because he's not a cerebral quarterback yet. Those situations should come on designed shot plays on early downs that, if a defense isn't caught off-guard, Trubisky can just throw the ball away and the Steelers live to fight another down without ruining a drive.

The other aspect that helps the Steelers is Trubisky's mobility. Per Next Gen Stats, Trubisky has been one of the best scrambling quarterbacks in the NFL since he entered the league:

If Trubisky's eyes aren't showing him the designed open look in a given passing concept, he also has the ability to convert with his legs. Those openings are much easier to see for a young, developing quarterback than whether a defense is in a cover 3 or disguising a cover 6 package. Here's one of those breakdowns from 2020 when Trubisky ran for 11 yards to move the chains, even running away from some of the Packers defense so that he could get to the sideline:

Those types of plays will also force defenses to consider threats that weren't available to the Steelers' offense with Roethlisberger in 2021, and potentially force more players to be committed to stopping his legs to open up easier passing opportunities around the field.

And as shown on the 36-yard bomb Trubisky threw to Miller against Washington in 2018, there's ways to combine both his legs and his arm as an asset to make things easier for the thinking part of Trubisky's game as well. Canada's style of offense has always looked like it would truly benefit from being able to have a quarterback move to force defenders in coverage to move with him or to help isolate different targets in coverage for easier decisions. That couldn't happen with Roethlisberger's non-existent mobility, but it can with Trubisky.

Watch this touchdown pass Trubisky threw against the Seahawks in 2018. The play is a designed bootleg for Trubisky to roll to his right and get three options of an underneath flat route by the tight end, Robinson running a corner route that starts by breaking inside to freeze Earl Thomas, and Miller, running a simple corner route to the pylon. The concept forced the Seahawks to honor Trubisky's legs, the flat route, Robinson and Miller. Trubisky didn't have to figure out a sophisticated seam to hit between two defenders. He just had to find which one had the best leverage to the left sideline and make the throw, or take off. He found Miller for the score:

These are the things that could change the dynamics of how Canada calls his offense.

But Trubisky is far from a proven commodity at quarterback and will still need to show he's capable of running the offense while limiting mistakes. The roster will most likely be built on a stronger run game than in 2021, and a defense that carries the team to most of its wins. At that point, Trubisky will just be asked to not be the player that can undo that game plan with interceptions, while being a capable quarterback who takes advantage of when a defense is beat by a concept.

That balancing act will determine whether or not Canada has a future as offensive coordinator, or if the team must gut its offensive coaching staff while searching for its future franchise quarterback in 2023.