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19 Jul 2013

Matching Up to 12

by Tom Gower

One of the tables you will see in Football Outsiders Almanac 2013 is performance based on most common personnel groups. We do this for a team and the opponents it faced. From this you can get a good general picture of how a team played and how teams matched up to them. But the limitations of space don’t permit us to go into detail on particular matchups.

Last month, I covered how teams matched up defensively to offensive 11 personnel (one running back, one tight end, three wide receivers). One of the things I learned in that column was virtually every NFL team played more sub package defense (five or more defensive backs) against 11 in 2012 than they had in 2011. Was that trend toward more sub-package defense part of a broader trend, or was it just the result of 11 personnel?

To try to find an answer to this, I looked at the defensive personnel packages teams played against offensive 12 personnel (one running back, two tight ends, two wide receivers). I knew from my research earlier in the offseason that the Texans had matched their base defensive personnel (four defensive backs) against 12 personnel over 95 percent of the snaps in 2011 and were still over 90 percent in 2012 even with Brian Cushing out for most of the year. The Titans, meanwhile, were in a sub-package defense against 12 personnel some 19 percent of the time in 2011 and increased that to 26 percent in 2012. From this small sample size, I guessed that there was a leaguewide trend toward playing more sub-package defensive personnel against 12 personnel.

As it turns out, teams did play more sub packages against 12 personnel in 2012, though only in the most technical sense. After spending 78.3 percent of plays against 12 personnel countering it with base personnel in 2011, teams spent a mere 78.1 percent of plays doing the same in 2012. Instead of almost every team playing more sub package defense, as was the case against 11 personnel, precisely half of the league played more sub packages against 12 personnel, while the other half of the league played more base defensive personnel. To illustrate this very mixed trend, here is how often each team played in base personnel on defense against offensive 12 personnel the past two seasons. To highlight the changes, I also included a column showing the percentage change in base defensive personnel from 2011 to 2012; a positive number means more base personnel, a negative one more sub package.

Team 2011 2012 Change
ARI 77.8% 79.8% 2.0%
ATL 88.6% 48.2% -40.4%
BAL 82.8% 88.5% 5.8%
BUF 55.8% 82.3% 26.5%
CAR 96.5% 87.4% -9.1%
CHI 89.9% 84.3% -5.6%
CIN 92.2% 86.2% -6.0%
CLE 90.7% 84.4% -6.2%
DAL 75.4% 89.6% 14.3%
DEN 77.9% 65.0% -12.9%
DET 92.4% 98.0% 5.6%
Team 2011 2012 Change
GB 45.9% 36.0% -9.8%
HOU 95.7% 92.7% -3.0%
IND 81.3% 83.4% 2.2%
JAC 86.6% 91.2% 4.5%
KC 80.1% 81.1% 1.1%
MIA 56.2% 67.6% 11.4%
MIN 84.7% 84.1% -0.6%
NE 58.7% 80.7% 22.0%
NO 83.7% 59.9% -23.8%
NYG 37.4% 79.9% 42.4%
Team 2011 2012 Change
NYJ 48.8% 56.8% 7.9%
OAK 66.7% 85.6% 18.9%
PHI 80.6% 90.1% 9.5%
PIT 90.3% 84.7% -5.6%
SD 89.3% 95.1% 5.8%
SEA 78.1% 77.0% -1.1%
SF 82.3% 58.3% -24.0%
STL 90.4% 73.3% -17.1%
TB 89.2% 67.2% -22.0%
TEN 81.0% 73.6% -7.4%
WAS 84.5% 89.3% 4.8%

A couple things stand out in that table. First: goodbye to the big nickel. The Giants seemed to be at the forefront of that trend for a number of years, and in 2011 played more sub package against 12 personnel than any other team in the league. That changed last year, as they played an above-average amount of defensive base personnel against 12 personnel.

Second, the Texans played just as much base personnel as I thought they did in 2011. As was the case with respect to 11 personnel, the Panthers played base defensive personnel the most, but the Texans were a close second. Things changed for the Panthers in 2012 against 11 personnel, and they did here, too, though not as dramatically. The team that played a lot more sub-package defense was the Falcons, a curious move considering how poorly their defensive backs tackled (as noted in the Atlanta chapter of FOA 2013, they ranked behind only the Eagles in blown tackle percentage). Then again, the Falcons had a much better DVOA in 2012 against 12 personnel with five defensive backs on the field than they did with four, so Mike Nolan (unsurprisingly) knew what he was doing.

Here are the full 2012 numbers for the most frequent defensive personnel package each team used against 12 personnel, how often they used that many defensive backs, and yards per play, success rate (from the defensive perspective, so greater is better), and DVOA that the most-used personnel grouping allowed against 12.

Team DBs Freq Yards per Play Success % DVOA
ARI 4 79.8% 5.2 62% -19.8%
ATL 4 48.2% 5.2 58% -16.0%
BAL 4 88.5% 5.6 51% 12.8%
BUF 4 82.3% 5.8 58% 15.7%
CAR 4 87.4% 5.0 57% -0.1%
CHI 4 84.3% 4.7 60% -26.3%
CIN 4 86.2% 4.8 56% -6.9%
CLE 4 84.4% 5.5 56% -1.0%
DAL 4 89.6% 5.8 54% 3.5%
DEN 4 65.0% 5.8 55% -2.1%
DET 4 98.0% 5.8 55% 6.4%
Team DBs Freq Yards per Play Success % DVOA
GB 5 44.5% 4.1 64% -33.9%
HOU 4 92.7% 4.1 65% -27.2%
IND 4 83.4% 6.3 57% 0.9%
JAC 4 91.2% 6.0 45% 22.7%
KC 4 81.1% 5.2 56% 5.2%
MIA 4 67.6% 5.6 56% 2.0%
MIN 4 84.1% 4.7 61% -14.5%
NE 4 80.7% 7.0 45% 25.7%
NO 4 59.9% 7.6 56% 23.6%
NYG 4 79.9% 4.7 56% -24.5%
Team DBs Freq Yards per Play Success % DVOA
NYJ 4 56.8% 5.1 53% 1.5%
OAK 4 85.6% 5.2 55% 11.7%
PHI 4 90.1% 5.0 60% -3.4%
PIT 4 84.7% 6.0 53% 10.3%
SD 4 95.1% 4.8 62% -6.0%
SEA 4 77.0% 5.4 57% -19.5%
SF 4 58.3% 5.5 56% -12.6%
STL 4 73.3% 4.6 59% -18.8%
TB 4 67.2% 5.5 54% -8.0%
TEN 4 73.6% 5.6 53% 7.0%
WAS 4 89.3% 4.8 57% -17.3%

While the Falcons played sub-package personnel the majority of the time, a plurality of their snaps against 12 personnel came in base defensive personnel, in case you're wondering why the Packers are the only team in the league listed with five defensive backs as their most common personnel grouping. Those are also the only two teams we have playing more than 20 snaps of dime against 12.

Finally, this lets us set up a comparison: How much did teams adjust what their defensive personnel was when the offense took a tight end off the field and added a receiver, going from 12 to 11? There are a couple ways we can try to answer this question, but I will choose the most straightforward way: the change in the percentage of base personnel.

Team Base v 12 Base v 11 TE to WR = DB %
ARI 79.8% 8.0% 71.8%
ATL 48.2% 2.6% 45.6%
BAL 88.5% 8.5% 80.0%
BUF 82.3% 3.3% 79.0%
CAR 87.4% 4.3% 83.1%
CHI 84.3% 3.4% 80.9%
CIN 86.2% 8.9% 77.2%
CLE 84.4% 6.2% 78.3%
DAL 89.6% 7.4% 82.2%
DEN 65.0% 6.4% 58.6%
DET 98.0% 10.6% 87.5%
Team Base v 12 Base v 11 TE to WR = DB %
GB 36.0% 1.3% 34.7%
HOU 92.7% 15.8% 77.0%
IND 83.4% 12.8% 70.6%
JAC 91.2% 10.2% 81.0%
KC 81.1% 8.5% 72.6%
MIA 67.6% 7.0% 60.6%
MIN 84.1% 3.3% 80.8%
NE 80.7% 9.1% 71.6%
NO 59.9% 3.4% 56.5%
NYG 79.9% 3.4% 76.5%
Team Base v 12 Base v 11 TE to WR = DB %
NYJ 56.8% 7.8% 49.0%
OAK 85.6% 3.6% 82.0%
PHI 90.1% 3.4% 86.7%
PIT 84.7% 19.9% 64.8%
SD 95.1% 9.0% 86.1%
SEA 77.0% 17.1% 60.0%
SF 58.3% 5.9% 52.4%
STL 73.3% 10.1% 63.2%
TB 67.2% 3.5% 63.7%
TEN 73.6% 4.0% 69.7%
WAS 89.3% 13.8% 75.5%

The teams that played base defensive personnel the least against 12 personnel, such as the Packers, show up with the least change in this chart simply because there was only so much room for them to change. By a more blended methodology, the Packers went from averaging 4.9 defensive backs on the field against 12 personnel to 5.5 against 11 personnel. They’re a bit of an outlier thanks to their heavy use of dime against 11, though. By contrast, the chart actually overstates how much the Falcons changed defensive personnel; they went from averaging 4.7 defensive backs against 12 personnel to 5.0 against 11 personnel. To pick a third team, the Lions went from averaging 4.0 defensive backs against 12 personnel to 4.9 against 11 personnel, so the straightforward methodology pretty accurately explains how their defensive look changed. Given I am trying to elucidate the change in matchups, I think the most straightforward method works pretty well.

I thought about concluding this little series with a further installment on how teams defended 21 personnel. As it turns out: every team in the league played base defensive personnel against 21 personnel over 80 percent of the time. With so little variation in matchups, I’ll leave how defenses fared against 21 to the 2012 Performance Based on Most Common Personnel Groups table to the chapter of FOA 2013 that is nearest to your heart.

Posted by: Tom Gower on 19 Jul 2013

8 comments, Last at 25 Jul 2013, 12:38pm by LionInAZ

Comments

1
by young curmudgeon :: Sun, 07/21/2013 - 2:11pm

It's probably too late already, but is there another terminology that could be used for the different alignments? My first impulse when I see "Matching up to 12" is "Hey, that isn't fair, you're only supposed to have 11 players on the field." Admittedly, that's stupid, but, in a game totally in love with overly complex jargon,
"12" seems like an awkward, unintuitive way to express the idea that the offense has two tight ends and two wide receivers. Maybe calling the "11" configuration "1-1-3" and the "12" configuration "1-2-2" or something like that...

I got used to "nickel" (after all, it means 5 defensive backs) and then "dime" (next step up from nickel) just fine, but I still don't even like "red zone." (What's wrong with 'inside the 20'?) So perhaps I'm not the best guy to grumble about fancy new terminology.

4
by Tom Gower :: Mon, 07/22/2013 - 11:28pm

"11" and "12" seem to be the generally-accepted and widely-used terms people around football use for the personnel groupings, which is why I used them. If they were my terms, believe me, I would have used something else rather than having to check every paragraph 5 times to make sure I didn't screw something up.

5
by Bobman :: Tue, 07/23/2013 - 1:44pm

I'm personally waiting for Christopher Guest to take a job as a offensive coordinator, just so he can say about his scheme, "This one goes to 13." (That's what, one RB and 3 TEs?)

8
by LionInAZ :: Thu, 07/25/2013 - 12:38pm

Don't the 49ers already use that formation occasionally?

6
by Noah of Arkadia :: Tue, 07/23/2013 - 2:04pm

It's not so hard once you understand the logic. Once you remove 5 OL and the QB, you have 5 players left. With 11 personnel if you add the digits -corresponding to RBs and TEs- you have 1+1 = 2 leaving you with 3 WRs. With 21, 2+1 = 3 leaving you with 2 WRs.

------
The man with no sig

7
by DisplacedPackerFan :: Tue, 07/23/2013 - 2:13pm

My issue was at first trying to remember the order of the numbers. Was it RB first? Was it TE first? Then I realized that order is alphabetical (R before T). Then my only issue was making sure I didn't transpose the digits with easy to make typos.

2
by Led :: Sun, 07/21/2013 - 7:17pm

This is very interesting. Of course, not every team's "12" package is the same. Differences in opponent personnel might have as much to do with how teams choose to defend the two tight-end set as the defensive philosophy of the team. For example, you need to defend the Pats differently from the 49ers.

3
by Tom Gower :: Mon, 07/22/2013 - 11:25pm

This occurred to me as well. If I have time, I'll look into it and may write something on if teams defend different offenses differently (e.g., more base v SF, more nickel v DEN, etc).