The Head of the Line

Which team is the best in the NFL right now?

That’s a tricky question in almost every season, but this year it is almost impossible to answer. It seems like with every week that passes we have a new answer to give, and ten games into the season there are still probably a half dozen teams that have a worthy claim to that title.

Early favorites like Denver, Philadelphia, and Minnesota have plummeted after hot starts. Seattle’s come on strong, but this is the same team that scored only three points against the Rams. New England is always in the conversation no matter how many of their best defensive players they trade away. If you asked around, the most common answer would probably be the Cowboys, but how confident can we be in a team starting a rookie quarterback and a defense that most people couldn’t name even a single starter from?

The NFL is always unpredictable, but this year feels as wide open as any in recent memory. Teams like Pittsburgh and New Orleans would be outside the playoffs if the season ended today, yet both have reason to believe they could get hot and steal a championship. Everyone is looking up right now and seeing nothing stable above them.

At least, that’s the way it feels. The standings aren’t any more imbalanced than we’re used to seeing, but it does seem like the best teams have at least one glaring flaw. Seattle’s offensive line, Oakland’s defense, Denver’s Trevor Siemian. From the beginning of the season we’ve heard that there are no complete teams, just a bunch of lopsided heavyweights that turn away whenever one side of the ball is on the field.

Everyone seems to be in agreement on this point, but that’s not good enough for me. Because I’m a nerd, I’m not convinced until I see some numbers to back these things up. I want proof, and to get that proof I’ll turn to my old friend DVOA.

For those of you who haven’t encountered this stat here or elsewhere, a quick primer. DVOA is a metric calculated by Football Outsiders using situational success on a play by play basis, which is then adjusted for level of competition. It is much more granular than most measures of offensive and defensive success, which are usually expressed in terms of points or yards allowed. If you’re really curious, you can read more here. If not, just skim down to the numbers below.

For simplicity’s sake, I focused only on the disparity between a team’s offense and their defense. This doesn’t capture when one piece of the unit is particularly wretched (the best example being Seattle and their so called “offensive line”), but it is a pretty good summary for teams like Atlanta, Denver, and Oakland.

DVOA is expressed as the percentage deviation from average. So if a team has an offensive DVOA of 10%, that means they are 10% better than a league average offense. Defensive values are inverted, so a defensive DVOA of 10% actually means that a team is 10% worse than average.

Using these numbers, it’s fairly straightforward to calculate a statistical measure of how large the disparity is between offenses and defenses across the league. Since defensive values are inverted, we take the sum of the two values to get the total difference between them (therefore an offensive DVOA of 15% and a defensive DVOA of 20% are 35% separated). Since for this analysis we don’t care which of the sides is the better of the two, we square these values to make them all positive, then average them and take the square root of this average to get the mean disparity between offense and defense.

That sounds like a lot, and if you don’t care about the math, then just interpret these numbers as follows: a bigger number means the average team is more polarized between their offense and their defense.

I performed this calculation for every year going back to 2004. For comparison’s sake, I used DVOA through Week 11 of each of these previous seasons. I also performed another similar but simpler calculation using each team’s DVOA rankings rather than the raw percentages. Take a look at the numbers below.

	Average DVOA Disparity	Average Ranking Disparity
2004	26%	15.3
2005	18%	11.4
2006	21%	13.8
2007	18%	11.2
2008	19%	12.1
2009	16%	9.0
2010	22%	11.7
2011	20%	13.3
2012	19%	12.2
2013	19%	14.2
2014	16%	13.3
2015	15%	12.3
2016	20%	16.1

At first glance, the numbers don’t really jump off the page. The DVOA disparity is high this year compared to the last couple, but it isn’t out of line with many of the seasons that came before. It’s the same as 2011, and less than 2010.

(Incidentally, both those years saw a team advance from the Wild Card round to a Super Bowl victory. Read into that whatever you want.)

We see a slightly different picture when we look at the second column. In terms of overall percentage spread this year doesn’t blow past the ones that came before, but when you look at the evenly spaced rankings, you see a different story. The average team is sixteen spots separated between its offense and its defense, by far the highest of any year since DVOA became available on a weekly basis.

This disparity is definitely interesting. The first explanation that came to mind was a decrease in variance, possibly due to a lack of extremely good or extremely bad offenses or defenses. And looking closer, the numbers back this up. The highest rated offense in the league is Dallas with a DVOA of 25.8%. The top defense is Philadelphia with a DVOA of -21.6%. Compared to the previous twelve seasons those would be the third lowest rated top offense and lowest rated top defense through the first 11 weeks.

The results can be seen some on the other end as well, though it isn’t as extreme. Detroit’s 19.4% defensive rating is one of the worst values in recent history, but Houston’s league last -21.7% offense is middle of the pack among the worst offenses of the past 13 years.

This is just one of the ways that this year looks distinctly different at the very top of the league.  There is only one team (Seattle) ranked in the top ten in both offense and in defense through the first 11 weeks, the first time that has happened in this sample. On the other hand, there are 10 teams ranked in the top ten in either offense or defense and ranked in the bottom ten on the other side of the ball, tied with 2004 for the most.

The trend is hard to miss. There are actually twelve teams in the league with a difference between their offensive and defensive DVOA of less than ten percentage points, but this collection of teams is not the finest in the NFL. Of them, only Seattle and Kansas City have a winning record. The rest are either mediocre (Tampa Bay, San Diego), disappointing (Pittsburgh, Green Bay, Carolina, Cincinnati), or downright terrible (Chicago, San Francisco, the Jets, Cleveland).

Balance is not a key to success in the NFL. The team with the widest gap is Baltimore, whose 30^th ranked offense has survived thanks to the 4^th ranked defense. The next largest gap goes to the team with the best record in the league. The top ranked offense of the Cowboys has elevated a slightly below average defense to a 9-1 record.

If the playoffs started today, the twelve teams represented would be New England, Baltimore, Houston, Oakland, Kansas City, Denver, Dallas, Detroit, Atlanta, Seattle, the Giants, and Washington. I already listed Seattle and Kansas City among the balanced teams, but of the other ten, only Detroit and the Giants have a separation of less than 20 percentage points.

There are balanced teams in the league this year, but these aren’t the teams that are finding success. The best teams are the ones that can find a way to dominate in one phase of the ball, a model that proved particularly successful for last year’s Super Bowl champions.

The numbers are there in front of us, and they are confirming what we’ve suspected all along. There is no team in the NFL that dominates on both offense and on defense, and every contender has major flaws. So the question becomes, where do we go from here?

The easiest answer is that I have no idea. In a year with this many unbalanced teams, the final results will likely come down to matchups. New England’s offense looks dangerous with a rejuvenated Tom Brady under center, but Seattle showed just how helpless they can be with no pass rush against a quality quarterback. Denver’s defense is nearly as good as it was a year ago, but against top defensive foes their inexperienced passer could sink them. Even Dallas showed signs of struggling against a mediocre Baltimore team that just so happens to have a powerful run defense that knocked their offense off sync.

Playoff seeding will be crucial to watch going forward. In a lot of ways it will be about luck, who draws the most favorable path going forward. Home field advantage matters as well, a small advantage that can’t be underestimated when margins are this thin.

There is another possibility as well, and it is one that might be unfolding already. The successes and failures of teams are not constant throughout the season, and it’s very possible for a team to pull itself together as the year goes along. The clear candidate right now is Seattle, the lone team that falls in the top ten in both offense and defense. Just three weeks ago they were a below average offense, but the improving health of Russell Wilson has brought their offense to a level nearly on par with their defense.

If I had to name the best, most complete team in the league, right now I would go with Seattle. But this season has been particularly fickle, and this could easily change by the time playoff season rolls around. Seattle’s offense could fall off again, or they could hit a matchup that can exploit their trash heap of an offensive line (the Vikings team that nearly knocked them out of the playoffs a year ago should be particularly terrifying).

Or someone else could step forward. Atlanta’s and Pittsburgh’s young talent could mature into league average defenses. Paxton Lynch could bring a spark to Denver’s offense. Joe Flacco could travel back in time to 2012 when he didn’t suck. And I will never, ever count out Bill Belichick scrapping together a quality defense.

This season feels completely wide open, and the numbers back it up. Right now almost every team in the league has reason to believe they can grab a playoff spot, and most have the potential to go farther than that. There is no big bad sitting at the top of the league, and that means that spot is open for anyone to claim.