State of Defense: Just How Bad is Seattle’s Defensive Line through Week 3?
All offseason, the defensive line has been a constant concern. Through 3 weeks of the 2020 NFL season, the eye test suggests that the concerns were indeed valid. In this article, I’ll go through various statistics and metrics to assess just how the defensive line has fared through Week 3. I’ll be using advanced data from a variety of sources: ESPN Analytics, Pro Football Reference (“PFR”), Football Outsiders (“FO”), and other widely available team statistics. I’ve chosen to stay away from more simple metrics, such as total pressures and sacks, as they don’t give a complete picture of the defense. At the end of the article, I will simply average the rankings for each metric for an overall defensive line ranking (I know this is a crude and imperfect way to quantify this data, but it is the simplest way to aggregate information into one number).
ESPN: Pass Rush Win Rate (“PRWR”)
Rank 12, 45% PRWR
(Simply put, PRWR calculates how often a pass rusher is able to beat a block within 2.5 seconds. Purely using pressure percentages and sack totals often doesn’t capture the whole story. If a team’s D Line wins within 2.5 seconds every time, but the opposing QB always throws a pass within 2.3 seconds every time, the team will have 0 sacks, but does that mean the team actually has a bad pass rush? No, right? The hypothetical team was simply a victim of circumstance, due to the low time-to-throw of the opposing QB.)
I was really surprised to see Seattle ranked this high, considering SEA only has 5 sacks on the season despite teams passing a league-high 155 times against them. I wonder how this metric accounts for blitzes, as SEA has blitzed 36.4% of the time (5th most) according to PFR. Surely, a free blitzer would count as a “win”, right? Either way, looks like SEA is getting pressure at a decent rate (possibly through lots of blitzes).
ESPN: Run Stop Win Rate (“RSWR”)
Rank 6, 33% RSWR
(RSWR calculates how often a run defender “wins”, and includes wins as successful gap fills, backfield penetrations, successful containments, and more, based on assigned responsibilities. Run defense is more nuanced and subjective than pass rush and ESPN acknowledges these difficulties in their model explanation.)
Not surprised here, as SEA is elite in run defense (more on that later). The eye test generally agrees with this stat as well. Ford, Reed, and Mone have done an excellent job in anchoring the line and keeping the LBs clean so they can make a tackle. We also often see penetration into the backfield for a TFL.
PFR: Rushing Yards per Attempt
Rank 3, 3.0 YPA
As mentioned above, Seattle’s run defense is elite. SEA ranks only behind PIT and TB in YPA and both ranked top 5 last season (PIT 3rd, TB 1st). Interestingly, teams have run against SEA only 67 times, 2nd fewest in the league (again behind PIT). While this could be a product of the opponent’s game script, it could also be a part of the game plan. After all, SEA gives up 8.5 passing yards per attempt, 4th worst in the league. Either way, the run defense has really turned itself around after giving up 4.9 YPA (5th worst) last season. A specific example would be holding NE to just 67 rushing yards (!) after seeing them demolish LV and MIA on the ground, racking up more than 200 rushing yards in each of those contests.
I know this isn’t a perfect measure of the defensive line’s performance, but I’d argue that run defense is MOSTLY attributed to the defensive line and linebackers. It’s also the primary role of DTs. Yes, it helps to have an All-World LB in Bobby Wagner and personally, I think Adams has been HUGE in turning around this run defense and I can count a number of times he’s been in on a TFL or a tackle for minimum gain.
PFR: Pressure Rate
Rank 16, 22.4% of dropbacks result in a pressure
(A pressure is defined as a hurry (QB threw ball earlier than intended or chased out of pocket), a QB hit, or a sack.)
Again, this was higher than expected, at least in my opinion, but falls in line with ESPN’s PRWR and yes, SEA’s high blitz rate may have something to do with this. 16th is by no means great, but given how woeful the pass rush has seemed at times, it’s encouraging to see the team with an average pressure rate.
Seattle ranks 28th in sack % at just 3.1% of dropbacks resulting in sacks, despite them ranking 16th in pressure rate. There have been a handful of times where a SEA defender has gotten their hands on the opposing QB, only to have them slip away. I remember a couple of instances against Cam Newton (he is incredibly hard to bring down, though) and most recently, Mayowa’s almost-sack on Dak Prescott right before Ryan Neal’s game-sealing interception. Hopefully some of these near-misses translate to sacks. I also noticed that Seattle tends to blitz less when they have the lead, electing to play more defenders in coverage. This felt especially evident last week against DAL and against NE.
FO: Rush Defense DVOA
Rank 4, -37.6%
Remember that on defense, the lower the DVOA the better. SEA’s 4th ranked run defense matches what we’ve seen in other metrics like RSWR and yards per rush attempt. Note that NE and DAL rank 2nd and 13th respectively in rushing offense DVOA.
Looking deeper into FO’s defensive line ratings, SEA ranks 4th in Adjusted Line Yards (“ALY”), which show yards given up by the defensive line. However, SEA ranks markedly lower at 13th, but still above average, in Power Success, which is percentage of successful runs converted with less than 2 yards to go on 3rd down, 4th down, or on goal. Similarly, SEA’s Stuffed Rank, percentage of runs going for no gain or worse, is 7th – still really good but lower than its ALY ranking. As FO points out in its disclosures, 2nd Level Yards and Open Field Yards are indicative of LB and DB play, both of which SEA ranks 2nd in. Like mentioned earlier, run defense in general is a team effort and while SEA’s LB and safety play certainly has contributed to the elite run defense, the defensive line seems to be doing fairly well in run defense.
Source: Football Outsiders
Further, FO breaks out ALY by direction. Notice how SEA ranks in the top 10 in rushes to the left side of the offense (right side defense) and up the middle, but terribly in rushes to the right side of the offense. Looking further at why the Right End ALY is so bad, it could be a result of small sample size, as only 4% of rushes against SEA have gone to the Right End. The Right Tackle direction, however, has a larger sample size, as 13% of runs have gone in that direction and could be indicative of a larger issue. If I’m not mistaken, that’s the side where Benson Mayowa lines up.
Source: Football Outsiders
FO: Adjusted Sack Rate
Rank 25, 4.2% adjusted sack rate
(FO’s Adjusted Sack Rate includes intentional grounding penalties and adjusts for down, distance, and opponent.)
FO’s sack metric is a little kinder to SEA than regular sack rate (28th, 3.1%). As noted earlier, sacks shouldn’t be only metric used to evaluate pass rush success, but given FO’s adjustments, I think it’s fair to include.
Final Results – Rank 11th
PRWR – Rank 12, 45%
RSWR – Rank 6, 33%
Rush YPA – Rank 3, 3.0 YPA
Pressure Rate – Rank 16, 22.4%
Rush D DVOA – Rank 4, -37.6%
Adj. Sack Rate – Rank 25, 4.2%
Honestly, I thought it would be worse. I included 3 metrics each for run defense and pass rush, so those two are weighted equally. We can debate about what is more important in the context of a good defensive line, but I made them equal for simplicity, as both are important to a certain degree. The biggest surprise to me is how seemingly “average” the pass rush is, despite all the criticism. As a fan, it often feels like the pass rush is lacking, but the metrics above state otherwise. The overall rank of 11 is heavily boosted by run defense metrics, but that shouldn’t be a surprise.
Below are the average ranks individually for run defense and pass rush:
Run Defense – Rank 4th
Pass Rush – Rank 18th
In summary, the run defense is elite. I thought the loss of Bruce Irvin might affect the run defense a little, but SEA held Ezekiel Elliot in check. We’ll see if rushes to the left side of the defense will continue to gash the defense. The pass rush was a lot better than I expected, though I hypothesize that both ESPN’s PRWR and PFR’s Pressure Rate are impacted the amount that SEA blitzes, and thus produce numbers that are more favorable to SEA’s favor. Also, while pressures can sometimes lead to errant or incomplete throws, they often do still end up as completions, especially against top tier QBs. Sacks are much more impactful (loss of yards, chance of fumble) and SEA simply isn’t getting enough right now. We’ll see if anything changes in the coming weeks.