Bills Come Back to Earth
NFL Week 6 - The Buffalo Bills remain the No. 1 team in our DVOA ratings, even after last night's close loss to the Tennessee Titans. But boy, has the gap between the Bills and the rest of the league narrowed compared to a week ago. The No. 2 team both overall and specifically on defense is the undefeated Arizona Cardinals, and the gap between the two teams is much smaller now:
|Buffalo-Arizona DVOA Gap, Weeks 5-6|
|Team/Unit||Last Week||Rk||This Week||Rk|
|Bills total DVOA||49.6%||1||38.2%||1|
|Cardinals total DVOA||31.3%||2||33.9%||2|
After last night's loss, we probably can say goodbye to those "Best Team in DVOA Through X Games" lists for the rest of the season. A week ago, the Bills ranked No. 9 on the all-time list of DVOA through five games, and No. 2 on the same list specifically for defensive DVOA. Now, the Bills rank No. 41 on the all-time list of DVOA through six games, and No. 14 on the list for defensive DVOA.
The Cardinals are also a lot more consistent than the Bills this year. Even though they finished just three yards away from a touchdown that would have won the game, the Bills end up with negative DVOA for the game (-20.6%) and it would be negative (-12.0%) even if we remove the adjustments for playing a below-average Tennessee team. The Bills also had negative DVOA for their Week 1 loss to Pittsburgh. Arizona, on the other hand, has been between 15% and 50% for every game this year. Only the Minnesota Vikings come out with a lower week-to-week variance in DVOA than the Cardinals. So Buffalo has three games better than any game Arizona has played... but also two losses when Arizona has none.
Buffalo also surrenders the No. 1 spot in DAVE, the metric we use for our playoff odds simulation that combines DVOA with preseason projections to get a more accurate projection of how a team will play the rest of the season. The defending champion Tampa Bay Buccaneers are now the top team in DAVE, combining their strong preseason projection with their current No. 4 rank in DVOA. The Bills are still our Super Bowl favorites, but the Baltimore Ravens have narrowly passed the Bills as our favorite for the AFC's No. 1 seed, 36.5% to 36.0%. The Bills have stronger Super Bowl chances than the Ravens because of their higher DAVE rating and because they have a better chance to finish with the No. 2 through No. 4 seeds given that the Ravens still face competition for the AFC North title while the Bills essentially have the AFC East sewn up.
Buffalo's loss affected a number of other teams because the opponent adjustments for playing the Bills defense were so strong before the Tennessee game brought them back to earth. For example, the table below says that the Kansas City Chiefs have the same ranking as they did a week ago, 14th. But yesterday, they did not. In the ratings I ran after the Sunday games, the Chiefs had moved up to 8.7% DVOA and ranked 11th. Changes in the opponent adjustments for playing Buffalo dropped Kansas City to 7.4% DVOA and back into 14th place. Pittsburgh also dropped a spot, from 15th yesterday to 16th today, and some other teams moved around because of small changes in the opponent adjustments not just for playing Buffalo and Tennessee but for playing all the other teams that have already played Buffalo and Tennessee.
Speaking of the Chiefs, we've got good news and bad news for Kansas City fans in this week's ratings. The bad news is that the Chiefs have fallen from the top spot in offense after a turnover-filled performance against a poor Washington defense. Tampa Bay is now our top offense for the season, followed by the Chiefs, the Rams, the Cowboys, and the Packers. The good news is that the Chiefs climbed out of the bottom spot on defense! Not only are the Chiefs no longer a historically bad defense, they aren't even the worst defense of this season! That spot belongs to the Jacksonville Jaguars, who have given up 6.3 net yards per play (29th in the league) to one of the easiest schedules of opposing offenses (also 29th in the league) with only two turnovers. Jacksonville's defense did improve a little bit this week with the win over Miami; Kansas City's defense just improved more and passed the Jaguars to move out of last place.
Back to discussing the top of our ratings: the Los Angeles Rams moved up from fifth to third this week but more significantly, their defense moved from 14th to fourth after clobbering the shorthanded New York Giants. (The Rams' offense actually got a little bit worse this week, somewhat countering some of the defensive improvement.) Green Bay moved up from 15th to 11th overall and it's worth noting that the Packers would be fifth overall if we didn't count their Week 1 debacle against New Orleans. Indianapolis moved up significantly from 24th to 15th after a huge win over Houston. Pittsburgh, Las Vegas, and of course Tennessee were also on the rise.
Moving the other way, we can start with the Dallas Cowboys falling from second overall to fifth after a close win over New England. The Los Angeles Chargers went from the team whose relatively low DVOA confuses people to the team whose even lower DVOA still confuses people, as they fell from 11th to 17th. Denver fell from 18th to 22nd, and Carolina fell from 17th to 25th.
Run Funnels and Pass Funnels
The Chargers also stand out for another reason, which is a very one-sided defense. Los Angeles now has the worst run defense in the league this year according to DVOA, passing Kansas City at the bottom of our rankings after the big loss to Baltimore. Yet the Chargers also have the fifth-best pass defense in the league! That's a huge gap. If you have read Football Outsiders for a long time, you know that passing is generally more efficient than rushing. That's why almost every team will have a higher pass offense DVOA than run offense DVOA, and the same goes for defense. But this is not the case for the Chargers defense. The Chargers defense allows -8.8% DVOA on pass plays but 9.6% DVOA on run plays, so running the ball against them is actually more efficient than passing it.
This is very rare. There are only two other defenses with the same split so far this season. Minnesota ranks third against the pass but 28th against the run, and allows better efficiency on runs than passes. The other defense with a similar split is Buffalo, but for a different reason. The Bills have been so good against the pass this year that it has been more efficient to run against them, even though they rank sixth in the league against the run.
Here are the defenses with the biggest gaps between their rank against the pass and against the run, in both directions. Teams that are better on pass defense are generally known as "run funnels" and teams that are better on run defense are known as "pass funnels," terminology that comes from fantasy analyst Adam Levitan.
|2021 Run Funnels as of Week 6|
|Team||Pass Def||Rk||Run Def||Rk||Dif|
The strongest team in the other direction is the Indianapolis Colts.
|2021 Pass Funnels as of Week 6|
|Team||Pass Def||Rk||Run Def||Rk||Dif|
Say Something Nice About the Lions
The Arizona Cardinals are undefeated and at the top of most non-stat based power rankings around the Internet. As noted above, we've got them second behind Buffalo. For the last undefeated team to be second in DVOA is not strange. More than half the 6-0 teams since 1983 were not first in DVOA, but most of the rest were second or third or something in the top five.
Most non-stat based power rankings will also have the Detroit Lions last. They're the last team without a win, after all. So you might be surprised to check out the full DVOA table and notice that they are currently 26th, ahead of six other teams. The Lions are not as horrible as you think! They've played a tough schedule, fourth in the league so far. They've also had those two games where they lost on long field goals at the end of regulation against the Ravens and the Vikings.
It turns out the Lions are one of the better 0-6 teams in DVOA history. Here's a look at the best teams in DVOA at 0-6 and how those teams finished off the year.
|Best 0-6 Teams by DVOA, 1983-2021|
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Here is the Football Outsiders Top 16 through six weeks of 2021, measured by our proprietary Defense-adjusted Value Over Average (DVOA) system that breaks down every single play and compares a team's performance to the league average based on situation in order to determine value over average. (Explained further here.)
OFFENSE and DEFENSE DVOA are adjusted for opponent and performance indoors and consider all fumbles, kept or lost, as equal value. Opponent adjustments are currently at 60% strength and will increase 10% each week until Week 10. SPECIAL TEAMS DVOA is adjusted for type of stadium (warm, cold, dome, Denver) and week of season. As always, positive numbers represent more points so DEFENSE is better when it is NEGATIVE.
DAVE is a formula which combines our preseason forecast with current DVOA to get a more accurate projection of how a team will play the rest of the season. DAVE is currently 65% preseason forecast and 35% actual performance for teams with five games played, and 55% preseason forecast and 45% actual performance for teams with six games played. It is not currently adjusted for any backup quarterbacks. (This is part of why Seattle is still in the top ten.)
To save people some time, please use the following format for all complaints:
<team> is clearly ranked <too high/too low> because <reason unrelated to DVOA>. <subjective ranking system> is way better than this. <unrelated team-supporting or -denigrating comment, preferably with poor spelling and/or chat-acceptable spelling>
Click here for the full table.