Through the first nine weeks of the season, Andy Dalton was one of the best quarterbacks in the NFL. His unexpected improvement was one of the keys to the Cincinnati Bengals’ perfect start. His struggles Monday night — just 203 yards on 44 dropbacks, plus an interception — were a big reason why Cincinnati surprisingly fell from the ranks of the unbeatens against Houston.
In fact, Dalton’s struggles against the Texans should not have been a surprise, for reasons that suggest the fifth-year quarterback could well bounce back against the Arizona Cardinals this week but will likely struggle once again in the postseason.
Familiarity Creates Problems
The problem for Dalton is he performs significantly better against opponents who have not played the Bengals recently. This phenomenon was discovered by Bengals analyst Joe Goodberry. Against what he terms “uncommon” opponents, those who did not play the Bengals earlier that season or the previous season, Dalton is an excellent quarterback who has a great deal of success. Against “common” opponents, those who have faced the Bengals previously, Dalton finds the going much more difficult. Table 1 has the basic details.
Table 1. Dalton vs. Common and Uncommon Opponents
| Comp. Pct. | Yards/Att | TD% | INT% | |
| Common Foes | 59.0% | 6.5 | 3.4% | 3.5% |
| Uncommon Foes | 67.1% | 8.0 | 6.7% | 2.5% |
Dalton completes a higher percentage of his passes, for more yards per completion, throws many more touchdowns, and throws fewer interceptions against teams that have not played the Bengals lately. Table 2 has the numbers for just 2015, adding Football Outsiders’ per-play DVOA metric and another factor, Dalton’s sack rate.
Table 2. Dalton v. Common and Uncommon Opponents, 2015 Detail
| Comp Pct. | Yards/Att | TD% | INT% | DVOA | Sack% | |
| Common Foes | 63.7% | 7.7 | 5.2% | 3.0% | 3.2% | 6.9% |
| Uncommon Foes | 68.3% | 8.6 | 6.8% | 0.6% | 47.8% | 2.4% |
More Than Just Opponent Adjustments
The simple explanation is that Dalton is faring worse because he is facing better defenses. Many of the Bengals’ common opponents are AFC North foes and other teams who have ranked highly in their division. Football Outsiders’ opponent-adjusted metrics, however, suggest this is not the case. Opponent adjustments say Dalton’s 2015 performance against uncommon opponents has been even better than the raw statistics suggest, while his performance against common opponents has been worse than it looks.
Opponent adjustments were a part of the 2014 story, but only a very small part. Dalton had a non-adjusted VOA of 15.7 percent against uncommon opponents against an adjusted DVOA of 14.4 percent and a VOA of -20.9 percent and DVOA of -19.8 percent. Adding in opponent adjustments explains a very small part of the difference last year, and none of it this year or in 2013. There really does seem to be something else going on.
Sacks Are Part of the Story
The last column in Table 2, on sack rate, is especially informative. This is one area Dalton has improved from his younger days. He took an NFL-leading 17 coverage sacks in 2012 according to Football Outsiders’ charting data. Dalton has done a much better job of avoiding sacks and especially coverage sacks the past three seasons, but he still gets sacked at a much higher rate by common opponents.
Table 2’s cumulative numbers conceal one very interesting detail. Dalton’s 2.4 percent sack rate in his five games to date against uncommon opponents breaks down as four sacks by the Seattle Seahawks and no sacks by any of the other foes. Meanwhile, Dalton has been sacked at least twice in every game against a common opponent.
This season’s sack data continues a trend from 2014. That season, Dalton had a personal adjusted sack rate of 6.1 percent against common opponents compared to just 2.4 percent against uncommon foes, who often did not even sack him at all. Whatever Dalton does so well against uncommon opponents is reflected here as well.
Deep Balls Are Part of the Story
One thing that stood out Monday night was how much Dalton struggled throwing the ball down the field. He completed just two of his nine attempts thrown more than 15 yards downfield. This is another theme that runs through the common vs. uncommon opponents distinction.
Dalton has been a better deep ball thrower this year against common opponents, with great success against the Baltimore Ravens most notably, but the splits still stand out. His worst deep games were against Houston and the Pittsburgh Steelers, while he has posted an above-average DVOA in deep passes against all uncommon foes.
Last season’s numbers are cloudy because of an injury-plagued season from wide receiver A.J. Green and the absences of tight end Tyler Eifert and wide receiver Marvin Jones, but 2013 shows just how much difference common and uncommon games can mean to Dalton’s deep ball performance. In uncommon games, Dalton had a DVOA of 156.9 percent and a success rate of 56 percent on deep passes, versus a DVOA of -20.1 percent and a success rate of just 28 percent against common opponents. To put that in context, Dalton against uncommon foes was the best deep passer in the league by a significant margin and the second-worst deep passer in the league against teams more familiar with the Bengals.
What It Means Going Forward
Andy Dalton is a much better player against teams the Bengals have not faced recently. In particular, he is sacked much less frequently and is a much more effective downfield passer. This is one reason the Bengals have fared so well in interconference play and why he could do well against the Cardinals on Sunday night and the St. Louis Rams the next week. The bad news is, the Bengals still have four common foes left to play in the regular season, and most of the likely AFC playoff teams — New England, Denver, Pittsburgh, and even Indianapolis — are common foes. After an inspiring start, Cincinnati could be looking once again at a disappointing result and another fast playoff exit.