It’s no secret that the Buffalo Bills should prioritize the offense during this critical offseason. But just how much disparity existed between offense and defense this past year? To check in, we’ll mostly compare using league rankings from the 2018 regular season. Each team plays 13 unique opponents during the regular season. In a league of 32, this means most statistics typically normalize.
To explain that statement, when you play nearly half the league there’s an excellent chance that most opponent measures will be near the average. For instance, playing against the top two passing defenses will impact your passing offense to some degree. But with 11 more teams (one-third of the league) left over to play, you will nearly always get a shot at bad passing defenses and mostly average ones. What this means is that a team’s individual passing offense rank should have a high degree of validity. Data is courtesy of the NFL and Pro Football Reference.
A lot was said about the Bills’ defense being very good to elite, and plenty of statistical evidence supports that. A lot of this sentiment comes from the volume-driven argument of yards per game. And indeed, the Bills came in second place in the league with 294.1 yards allowed per game. Only Buffalo, the Baltimore Ravens and Chicago Bears came in under 300 yards. And the fourth place team was all the way up at 309 yards per game. While the above facts are true, volume stats are incredibly flawed as they are highly dependent on other factors. A team with an elite offense would keep the defense off the field and give a major assist to yardage stats, for instance.
So before we explore defensive rankings, let’s take a peek at how long the Bills’ unit was on the field. With a near perfectly average time of possession (14th in the NFL), the Buffalo defense didn’t get any hindrances or boosts using that metric. For plays, the league average defense was on the field for 1,007 snaps. Buffalo’s defense saw 968, which was the fifth-fewest in the league. So either the Bills’ offense was good enough to give them a roughly 4% decrease in snaps, or the defense was good at getting off the field.
A better metric might be the number of drives faced. In that category, Buffalo saw 189, or third-most in the league. With the third-most drives and fifth-least amount of snaps, the clear insinuation is that defense deserves the credit for the lower snap counts. Backing this is the fact that the Bills allowed 2.1 fewer first downs per game than league average, which was the fourth-best rate in the league.
Let’s look at yards allowed again but on a per-play basis. Overall, the team allowed 0.74 yards less than league average (3rd best). Splitting by play type they allowed 1.06 yards less per pass and 0.24 yards less per rush than league average (third- and tenth-best respectively).
Time for some miscellaneous stats. The Bills were the fourth-best team at interceptions when looking at per-passing-attempt rates. While not spectacular, they were tied for 15th in sacks per pass attempt. They were eighth-best at stopping their opponents on third down and tied for 14th place stopping teams on fourth down.
It seems like they should be in elite territory, but one metric flies in the face of that claim. The Bills allowed 0.1 point per game more than league average. Falling in at 18, that puts them in the pretty average category. They also were bad (30th) at red-zone defense and average (17th) at goal-to-go defense.
Before we look at offense, let’s examine a couple numbers that speak to the symbiosis between the three phases of the game. Opponents’ starting field position was at the 32.6 yard line. That’s worst in the league. That suggests a lot of shorter fields to defend. Despite this disadvantage, the Bills allowed 1.83 points per drive. While that’s only tied for tenth place, being above average when considering the poor starting field position speaks volumes.
The most important statistic is probably the best way to start. The Bills were 6.5 points per game worse than league average. That was the third-worst. Just to compare the volume stats, they were 30th in yards per game. An appalling 31st in passing was offset to some degree by falling in at ninth for rushing. To be fair, with Josh Allen the definitive best rusher on the team, the ninth-place ranking isn’t exactly something to hang their hat on.
To break down by amount of time on the field, the Bills had 1,008 snaps. That was only one more than league average. For passing they remain at 31st in the league per play with 0.86 yards less per pass than average. Rushing falls all the way to 21st in the league per play (0.18 yards less per play than average). The Bills had the worst interception rate in the league and were 21st in sacks per passing attempt.
Only five teams had fewer first downs during the year than the Bills. This is mostly due to being third-worst in the league on third-down conversions and second-worst on fourth down. Interestingly, they were 16th in red-zone conversions and were the fifth-best team in goal-to-go situations.
Looking at drive data, the Bills’ offense had 193 drives, which was third-most in the league. They were unfortunately sixth-worst in plays per drive and third-worst in yards per drive. So while they had a ton of opportunities, they didn’t make good use of them. Circling back to the all-important metric, the Bills were third-worst in scores per drive.
The offense and defense closely mirror each other. Specifically, each side of the ball saw a high number of drives, but a low number of plays and low yardage per drive. What that means is that both sides of the ball routinely got off the field quickly. That’s only a positive for defense unfortunately.
This isn’t to say that the offense isn’t without building blocks and the defense isn’t without weaknesses. These mirror each other as well with the surprising rates when it comes to red-zone and goal-to-go scenarios. Regardless of facts such as these though, it’s glaring how much more work the offense needs.