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Data Entry: Bears Offense Found Better Balance in 2nd Half of 2017

| January 8th, 2018

When the Bears were on their bye week back in November, I looked at Chicago’s play-calling tendencies over rookie quarterback Mitchell Trubisky’s first four starts. In that study, I found that Dowell Loggains’ offense had been incredibly predictable through those four games. The team basically ran the ball if it was 1st or 2nd down and 10 or less and threw it if it was 2nd and 11+ or third down and anything.

This is obviously not a sustainable way to run an NFL offense, so let’s look at how those trends may have changed in the 8 games the Bears played after the bye. As before, all statistics come courtesy of the fantastic¬†NFL play finder¬†from Pro Football Reference.

1st down

In Trubisky’s first four starts, the Bears ran it 72% of the time on first down, but those numbers shifted dramatically following the bye. They actually passed more than running on 1st down in the last 8 games, with only 46% of their 1st downs featuring runs (I should clarify here that throughout this article passing plays are those which were called to be a pass, so either a pass attempt, sack, or QB rushing attempt, while runs are rushing attempts by anybody other than the QB. This assumes all QB runs are scrambles, which might slightly skew the data, but the Bears didn’t call many designed runs for Trubisky this year).

I was very surprised to find that the Bears ran it less than half the time on 1st down after the bye, but it does make sense when you consider they spent a good portion of several games trailing and trying to catch up. If you only look at the first three quarters, when game situation will not impact play calling as dramatically, the Bears ran it 53% of the time on 1st down. This is still not nearly as high as I expected, and actually feels about right for a well-balanced but still run-based offense.

In terms of effectiveness, their 91 1st down runs gained 381 yards, an average of 4.2 yards per attempt, while their 109 pass plays gained 618 yards, an average of 5.7 yards per play (including sacks and scrambles). These are both respectable but not fantastic numbers. For comparisons’ sake, the Bears averaged 5.2 yards per run and 8.1 yards per pass play on 1st down in 2016 with a 48% run rate.

2nd down

When it comes to 2nd down, context is needed. A 3 yard gain is great on 2nd and 2, pretty good on 2nd and 5, and awful on 2nd and 10. With that in mind, I split the data into 4 groups based on the distance required to get a 1st down. The table below shows the results.

Just like first down, we see a number of differences between Trubisky’s first 4 starts before the bye and his last 8. The play calling on 2nd and short (mostly run) and 2nd and 11+ (mostly pass) hasn’t changed much, but the balance is much better when it’s 2nd and between 3-10 yards. In Trubisky’s first 4 starts, those were still more than 70% run, whereas now they are much more balanced, indicating a greater trust in Trubisky to make the offense work (more on that in a future article).

Another difference we see is an improved offense on 2nd down. In Trubisky’s first 4 starts, the Bears averaged less than 2 yards per play in 5 of these 8 categories. There’s still not a lot of success here, but it’s a bit better than it was in Trubisky’s first 4 games. Overall, they averaged 4.8 yards per play on 2nd down in the last 8 games, which is a nice improvement from the 2.6 yards per play they averaged on 2nd down in the 4 games before the bye.

If you look back at 2016, the Bears averaged 5.2 yards per play on 2nd down. That wasn’t exactly a top-shelf offense, but it was still noticeably better than 2017’s version on both 1st and 2nd down, which feels right considering how painful watching Chicago’s offense was for large parts of this season.

3rd and 4th down

I grouped 3rd and 4th down together because the 4th down sample size was too small to do on its own, and on both downs the objective is the same: pick up a 1st down. Because of that, I ignored yards per play, and just focused on how often they met that objective and moved the chains.

Here we don’t see a lot of balance, but that’s to be expected. You have the option of either running or passing when you only need a yard or two, but otherwise are pretty much throwing the ball if you need to get a first down. I might like to see the Bears try to run a little bit more often on 3rd and 3-4, but it’s hard to argue with the lack of balance overall given the context.

The biggest thing I note here is how often the Bears are behind the chains. Only 17% of their 3rd downs come in short-yardage situations, while 55% of them come needing 7 or more yards. While those are actually an improvement on Trubisky’s first 4 games (8% short yardage, 67% 7+), that is still far from a winning ratio. This to me is the biggest single statistic to highlight Chicago’s offensive futility in 2017.

If there’s one area where we see some improvement, it’s avoiding the 3rd and extremely long situations. 40% of Chicago’s 3rd downs in the 4 games before the bye came needing 11 or more yards, while that dropped to only 26% after the bye. Still, more than 1/4 of Chicago’s 3rd downs in the final 8 games came with them having lost yardage total on 1st and 2nd down. To put it mildly, that’s not good.

In Trubisky’s first 4 starts, the Bears were able to convert on 3rd and 7-10 just over half the time. I said at the time that was likely due to a small sample size (13 plays) and would not continue, and we certainly see that here.

One area where the Bears did improve their 3rd/4th down efficiency was in 3rd and medium (3-6 yards). They converted half of those chances here, compared to only 31% in Trubisky’s first 4 starts.

Sack Trends

One additional area I would like to highlight are when Trubisky got sacked. He was sacked a whole lot this year, including 21 times in 8 games after the bye. That’s not good, which is not entirely surprising given a rookie quarterback playing behind a banged-up offensive line and frequently playing catch-up and behind the chains.

But one thing I noticed that struck me as a good sign is when Trubisky took those sacks. 6 of them came on 1st down (5.5% of dropbacks), 2 on 2nd down (2.2% of dropbacks), and 13 on 3rd or 4th down (13.8% of dropbacks). It’s good to see that most of the high sack rate is coming from situations when Trubisky needs to hold the ball to make a play.

It’s worth noting that this matches the NFL trend. QBs as a whole were sacked on 5.6% of dropbacks on 1st and 2nd down and 9.7% of dropbacks on 3rd and 4th down in 2017. So while Trubisky took a whole lot of sacks in 2017, he was actually sacked at a lower than average rate on 1st and 2nd down. That 14% on 3rd and 4th down number is alarmingly high, but might be a function of the Bears being behind the chains so frequently in those situations.

Lessons Learned

Complaints about the offensive balance have been everywhere from Bears fans this season. In Trubisky’s first four starts, they were warranted. In the last 8, it appears that they were not, at least when looking at down and distance trends. There are other legitimate predictability complaints that can be made-like the fact that the Bears ran it only 13% of the time when they were in shotgun (per NFL savant)-but it appears this is one issue that they did in fact fix after the bye.

Of course, the problem is that fixing this did not fix the offense, but that is to be expected when you are playing with a rookie quarterback, banged-up offensive line, and terrible collection of pass targets. Those are all the ingredients for a bad offense, though you can make a pretty good case that the play calling certainly didn’t help.

With John Fox fired and Dowell Loggains on his way out the door, these trends won’t really teach us anything about the Bears for next year. Once the new coaching staff is put in place, I’ll probably look at similar numbers for where the head coach and/or offensive coordinator were in 2017, but that might not carry over all that much either since they’ll be working with different personnel in Chicago.

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