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| Havoc. ©Getty Images, 2015. |
Pioneer Bill Connelly of Football Study Hall defines Havoc as the percentage of plays in which a defense makes a tackle for loss, forces a fumble, or defenses a pass (by interception or break up). Connelly notes that hurries on the QB or QB hits would be included in Havoc if the stat was more consistently recorded. As I often do, I began wondering if there were other, more reliably registered statistics that could be included to account for pressuring of the QB.
Kentucky-Tennessees game are required viewing for all KY residents. During the 2015 football iteration, the idea of considering in Havoc holding against offensive lineman happened. On their last drive of the 3rd quarter, UK O-linemen were penalized for a block in the back and a hold and also surrendered a sack. UK’s first drive of the 4th quarter produced two more holding calls and the next drive ended when UT recovered a forced fumble; the previous two drives concluded with a punt and a turnover on downs, respectively. UK scored zero points on those three drives that spanned 16 plays (i.e., excluding penalty-plays and punts).
If you happened to see these sequences you would know the UT front-7 were Kieth-Moon-in-a-hotel-room in the UK backfield. Thusly, the UT defense would receive a Havoc rating of 18.8% for those three possessions (3/16)—slightly better than the 2015 national average of 16.1%. However, if we also include those 4 penalties in that equation, UT’s defense nearly doubles Alabama’s nation-leading 23.1% with a suffocating 43.8% Havoc.
Speaking of the Crimson, I watched their D generally smother LSU’s hopes of moving the chains forward. In the fourth quarter, LSU QB Brandon Harris completed a pass for 2 yards to ineligible left tackle Jerald Hawkins—an illegal touching penalty Saban declined. Upon seeing that, I thought that intentional grounding may also provide an alternative measure of QB pressure, as well.
I had zero desire to gather enough college game play-by-play summaries to warrant a reasonable sample. So I started with NFL play-by-play data from 2014 and 2015. I inspected correlations between game-by-game sacks allowed and offensive holding penalties (not per game, i.e., n = ~1400). Found no appreciable relationship there nor between sacks and false starts. I supposed I could have computed game proportions but was feeling uninspired so I shifted my focus to the season in aggregate.
That the NFL provides cumulative QB hit data is a benefit of using seasonal data. Likewise, I serendipitously discovered NFL Penalties dot com which allowed me to extract team-offensive lineman holding penalty data. I also extracted intentional grounding penalties. Plus, the site offers declined and offsetting penalties, which I included in the analyses. Next, I computed several proportions for all NFL teams 2009 through 2014:
- O-lineman holding calls / total offensive plays;
- intentional grounding calls / (pass attempts + sacks);
- QB hits allowed / pass attempts. I excluded sacks from the denominator because a TD pass and QB hit can occur on the same play whereas a sack ends a play. Similar distinctions have been made in the literature; and
- team totals for QB rushing attempts, which exclude sacks. I expected that this might somehow interact with the aforementioned variables.
Next, we regress QB hits onto QB rushes and obtain the residual values (i.e., the values if the two variables are unrelated), R2adjusted = .062, F(1,190) = 13.57, p < .001. We then regress O-Lineman holds onto QB rushes and obtain those residual values, R2adjusted = .03, F(1,190) = 6.96, p = .001. Intentional grounding was unrelated to QB rushes.
Lastly, we regress the O-Linemen holding residuals onto QB hit residuals. This regression revealed that, when controlling for QB rushing, QB Hits accounted for 4% of the variance in O-Linemen Holding penalties, R2adjusted = .04, F(1,191) = 8.6, p = .004. Similarly, when controlling for frequency of QB rushing, QB hits accounted for 2% of the variance in Intentional Grounding penalties, R2adjusted = .02, F(1,190) = 4.76, p = .03. More ecologically, when intentional grounding and O-linemen holding penalties increase, it is expected that QB hits are probably increasing.
The explained variances are paltry, indeed, however significant. This finding would potentially be alleviated, or at least a more sound explanation elucidated, if the variables were examined on a game-by-game basis. I checked and OL experience was inversely related to the penalties and to QB rush frequency. I could have controlled for experience but declined to do so since correlations were weaker than each of the others reported above.
It is also worth noting there is a meager relationship of holding with sacks that is negated when controlling for QB rush rates. Likewise, either controlling for or ignoring the influence of QB rush frequency, OL holding calls are essentially unrelated to negative rushing rates (i.e., negative rushes / rushes). This latter point underscores another shortfall of the current examination: In future analyses, it would be beneficial to separate OL holding penalties for pass and rush plays. Lastly, the data examined here is from NFL data. It may be the relationship of these penalties and QB hits is more pronounced or altogether absent in the college game.
In conclusion, I advocate here for, if not the inclusion of, then the further analysis of the effect of including opponents' holding penalties by offensive lineman and intentional grounding penalties in the calculation of college football Havoc rates. I would lean to the latter because intentional grounding penalties are infrequent and generally resultant of a QB overwhelmed by the pass rush. I also wonder if blocked kicks and punts should be included in Havoc rate. Although a distinction must be made between special teams and defensive, blocks do occur on defensive special teams plays. Also, D-Linemen and LBs tend to lead the nation in blocked kicks and punts.
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