A Complete Breakdown of the Quarterback Position’s Efficiency for 2018

The offseason is the perfect time to do a deep dive into what exactly we saw on the field last year, so today I want to look more closely at how Chicago’s QBs performed in 2018. To do so, I’m going to compile all of the information about individual targets from The Quant Edge and use it to see what we can learn about QB play as a whole.

Before we begin, I want to note two limitations.

This doesn’t split data into individual QBs, so unfortunately I can’t separate out the games Trubisky played and use only those. Still, Trubisky accounted for 85% of Chicago’s pass attempts in 2018, so this should still be useful to help us generally learn more about him.
This data only includes WRs and TEs, so I will not be able to incorporate any information about the 132 pass attempts that went to RBs (and Bradley Sowell). I really wish they included Tarik Cohen in particular, considering he finished 3rd on the Bears in targets, but no such luck.

With that said, let’s get started.

Route Efficiency

How effective were Chicago’s QBs targeting various routes?

That data can be seen in the table below, sorted from most to least targeted. I also highlighted routes that were particularly efficient in green, and routes that were particularly inefficient in red.

A few thoughts:

The Bears loved their go routes, but they sure didn’t work well in 2018. As previously noted, Trubisky had issues with deep accuracy, and maybe that was part of the problem. And you can argue there is value in go routes to back the defense off. But still, 26% completion rate is not acceptable for a route they utilize that frequently, and there were 5 interceptions thrown on go routes as well. If you’re looking for one bright spot on go routes, Allen Robinson caught 40% of his targets for over 16 yards/target.

Trubisky struggled throwing the deep ball last year, so it’s not surprising that another deep route – the post – finds itself in the red either. Thankfully the Bears didn’t throw this one as often, so it wasn’t as huge a deal. One player who did excel on posts was Trey Burton, catching all 3 balls thrown his way (small sample size alert for much of this data on individuals) for 55 yards.
Given Trubisky’s deep ball struggles, it’s notable that there are two deep routes (target depth >15 yards) where the Bears did well: crosses and corners. Both of these, despite being fairly deep, still had a pretty high completion percentage, and thus a very high yards/attempt. Maybe this is a small sample size issue, but it’s worth trying a bit more of them in 2019 to see if that carries over.
Anthony Miller was particularly dangerous on these routes, combining to catch 9 of 13 targets for 17.6 yards/target. I’m assuming he will get a bigger share of the targets next year, so continuing to use him here could be a natural way to switch some of those deep routes and improve efficiency (assuming that small sample size trend continues).
Switching to shorter routes, the Bears did really well on slants and struggled on digs. The slant data is pretty much all due to Allen Robinson, who received 12 of the 22 total targets. The digs don’t make much sense to me; they’re basically shorter crossing routes, and the Bears excelled on those. Trey Burton in particular struggled here, catching only 1 of 5 targets for 7 yards. Maybe the problem was in not picking up yards after the catch (YAC) on this short route; YAC was generally not very good for the Bears in 2018, and combining poor YAC with a short throw equals an inefficient route.
I’ll randomly note that Adam Shaheen was really good on flat routes, though again sample size is an issue. He caught all 4 targets for 34 yards, while everybody else combined to catch 8 of 12 targets for 40 yards.

WR vs. TE

How did QBs used WRs and TEs differently?

The data for various routes can be seen in the table below, sorted from lowest to highest % of targets that went to TEs compared to WRs. WR-heavy routes are highlighted in blue, and TE-heavy routes in orange.

(I’ll note I set a threshold of 10 total targets for data to be included.)

A few thoughts:

Overall, 24% of the total targets to WRs and TEs went to TEs. So that gives you a baseline to see which routes were utilized more by TEs and WRs.
Many of these have small sample sizes, which can of course skew the numbers a little bit. Have to throw that caveat in there.
The most WR-heavy routes are mostly deep routes (go) and routes that utilize the threat of deep routes (screen, comeback). The obvious exception is slants, which are mostly Allen Robinson, as previously noted.
The TE-heavy routes are mostly underneath, as the drag and flat are short routes and the dig a medium one. Corner routes are the notable exception there, as the average target depth was more than 15 yards for TEs and WRs alike. It appears that’s the go-to route for the TEs when they are going deep.

Man vs. Zone

How did QBs fare against differing coverages?

The data can be seen in the table below.

A few thoughts:

In general, the QBs really struggled throwing into press coverage. They tended to favor targeting WRs over TEs in these situations, but didn’t throw it effectively to either group.
TEs were generally very effective against zone, and saw the largest % of targets there, while WRs were most effective against man coverage. A large part of that was due to Allen Robinson and Anthony Miller, who both excelled against man. Both had a completion % in the 50s, but yards per target of 9.2 (Robinson) and 13.3 (Miller), indicating they were able to make big plays downfield by beating their man.
Look at the TD/INT numbers for zone. Yikes. I fully expect a big part of that is due to Trubisky’s accuracy issues, as nearly half of his interceptions were due to missed passes. If you overthrow against man coverage, it’s an incomplete pass. If you overthrow against zone, it’s an interception. I will be very curious to look back at man/zone splits after 2019 and see how they might have changed as Trubisky progresses.
Teams switched to more zone looks as the season went along to take away Trubisky’s running and make him beat them with his arm. Based on this data, he was able to successfully attack the zone in terms of completing passes and picking up yards, so fixing a few of those errant throws to cut down on interceptions will force defenses to pick their poison and make the offense much more difficult to defend.