2017 DVOA by Routes: Defense

by Scott Kacsmar

In Part I of our look at 12 of the NFL's most common pass routes, we focused on the production of individual receivers. In Part II, we looked at last year's qualified quarterbacks. In our final part of this study, we are turning our attention to defenses, with an emphasis on touchdowns and interceptions.

While the first two parts used receiving DVOA, which does not penalize for interceptions, the following tables will use team defense DVOA credit the defense for those picks. This is why the DVOA will look a bit different in this part. (Sacks and plays with no intended receiver are still absent.) Also, this is from the defense's perspective, so negative DVOA is better here.

Touchdowns and Interceptions by Route

Our first section is a look at touchdowns and interceptions on all 22 route types with at least 200 attempts last season (including defensive pass interference penalties). We have 426 interceptions instead of the season's total of 430, because there were four interceptions with no route data where no intended receiver was assigned. If you are curious, those were interceptions thrown by Carson Wentz, Jameis Winston, Matthew Stafford, and Bryce Petty.

In most tables in this essay, defenses will be ranked by DVOA from most negative (best) to most positive (worst). However, in this first table showing overall route data, we've ranked the stats in "offensive order." (High DVOA, high touchdown rate, and low interception rate are good and ranked closer to No. 1.) In 2017, the league's average touchdown rate was 4.2 percent and the average interception rate was 2.5 percent. If we view the average touchdown pass on equal ground with the average interception -- and ESPN's win probability data strongly supports that for recent seasons -- then let's consider the trade-off involved with each route. I took each route's touchdown rate and subtracted the league average of 4.2 percent. I then took each route's interception rate and subtracted it from the league average of 2.5 percent. Finally, I added the two differences together to get the trade-off in percentage points, and that is the stat that the table is sorted by, from most advantageous to least.

There were some differences in how Sports Info Solutions charted routes in 2017, including the split of fades into back-shoulder throws and the addition of the highest DVOA route in the deep cross, but we found some similar results in 2016. For starters, the dig, curl, and comeback were once again the only three routes to have a negative trade-off of more than two percentage points in throwing touchdowns and interceptions. The post route, despite producing the second-highest DVOA, led to the highest interception rate for the second year in a row, which might explain why we don't see it that often. Similar things could be said about corner and seam routes, though the corner route has been very successful. It had the highest touchdown rate (14.1 percent) and the best trade-off (+9.3 percent) last season, and would have been the overall leader again had we not introduced the back-shoulder fade.

When you look at the yards per attempt for swing (4.47) and flat (5.12) passes, you can see why that is thought of as poor offensive play. An offense putting up those YPA numbers would be among the league's worst every year. However, if you think of those plays relative to rushes that are usually going to be around 4.0 to 4.5 yards per carry, then they're actually not so bad. That's why those throws, so often to running backs, should be thought of as extensions of the running game. No passing offense should build around these plays, but sprinkling them in from time to time is absolutely acceptable. Also, there has been just one interception on a swing pass in the last two years, so they are very safe plays.

Defenses vs. the 12 Most Common Routes

We did not include columns for touchdowns or interceptions in the following tables due to the numbers being fairly small for everyone. There were only 22 instances where a team allowed at least four touchdowns, and 10 instances of at least four interceptions, on any given route type.

Curl

We know defenses are less consistent from year to year than offenses, so our search for consistency with these numbers was going to be a difficult one. The curl did have the third-highest correlation among the 12 routes for defensive DVOA from 2016 to 2017, but it was a negative correlation and a small one (-0.17). The curl seemed to offer the best opportunity just because it's the most common route, with every defense facing at least 57 of them. That team with 57 was New England, which finished 31st in DVOA after finishing 32nd in DVOA a year ago. Ah, there's something consistent, which you might come to expect from Bill Belichick and his tradition of bend-but-don't-break defense. Losing coordinator Matt Patricia and top cornerback Malcolm Butler may throw in a few wrinkles to the 2018 defense, but it wouldn't be surprising if the Patriots were soft against the curl again. On the plus side, the Patriots only allowed one completion of over 20 yards (22 yards by Petty and the Jets) on curls last year. It's not the worst route to struggle with.

The Patriots and Cowboys were two of the five defenses to allow two touchdown passes on curl routes last year. No one allowed three scores. In 2016, Dallas allowed curls to be completed 85.6 percent of the time, the worst defensive rate in the league. In 2017, Dallas was last again at 80.4 percent. Throw in the way Dak Prescott doesn't get any YAC on his curls, and this has been a route that hasn't gone Dallas' way on either side of the ball the last two years.

The Chargers were picked on the most with 114 curl routes, but finished ninth in DVOA. They'll miss Jason Verrett this season, but it's not like they don't have experience playing without him. The cornerback has only played in 25 games since he was drafted in 2014. New Orleans hopes for great health for many years to come for Marshon Lattimore; the Saints finished first in DVOA after allowing the lowest YPA (5.59) and completion rate (63.5 percent) on curl routes. The Chargers and Saints tied for second place with four interceptions on curl routes, but Pittsburgh led the league with five intercepted curls, including three off of Marcus Mariota in Week 11.

The Seahawks tackled curls the best, allowing just 1.8 YAC in the swansong for the Legion of Boom secondary. The Rams didn't have a lot of weaknesses on defense last year, but they did allow the most YAC (5.4) on curl routes.

Out

We can come right back with a compliment for Wade Phillips' defense. The Rams led the league with three interceptions on out routes. Even though Miami allowed the most touchdown passes (four) on out routes, it also allowed the least YAC (1.1) to finish second in DVOA, trailing only Washington. Miami also finished third in DVOA on out routes in 2016, so that has been a good area for Adam Gase's defense. It was actually the Eagles that allowed the most YAC (4.0) on out routes, but Philadelphia still finished 10th in DVOA as one of nine teams that did not surrender a touchdown. The Jets were the only defense to allow a completion rate lower than 50 percent, but they also faced the deepest outs at 9.6 yards.

The Browns were largely terrible against out routes, allowing the highest YPA (7.74) and completion rate (72.5 percent). The only reason the Browns didn't finish last in DVOA on out routes for the second year in a row was thanks to the Steelers, who finished lower due to adjustments for down-and-distance. For example, the Steelers had a brutal 62.0% DVOA on second down on out routes, while Cleveland was 21st in the league at 3.7%. Even the Jaguars were surprisingly weak against out routes, finishing 30th in DVOA and 30th in completion rate (71.7 percent). It's the only major route where the Jaguars did not finish in the top 20 in DVOA.

Interestingly enough, the bottom five teams in DVOA all appeared among the 10 teams that faced fewer than 50 out routes,. The Chargers faced the fewest (41) while the Vikings (73) faced the most out routes.

Dig

For the second year in a row, an AFC West team faced the most dig routes, but it was Kansas City (52) instead of Oakland in 2017.

Teams in the same division face a lot of the same opponents in a season. That schedule correlation may have something to do with the AFC North having four of the five lowest totals of dig attempts in 2017, including the two fewest in Cleveland (20) and Pittsburgh (23). The Steelers excelled against these routes with the best DVOA (-75.6%) in the league thanks in part to having the most interceptions (four).

Deshaun Watson wishes he could throw dig routes against his own defense. The Texans finished last in DVOA after allowing a staggering 77.8 completion rate and 13.4 YPA on 27 dig routes. At least there was only one touchdown pass allowed. The Cardinals allowed the most touchdown passes (three) on dig routes while only three other defenses (Giants, Chiefs, and Cowboys) allowed multiple scores. The NFC East happened to play the two West divisions last year.

A year after Seattle allowed the highest completion rate (76.9 percent) on dig routes, the Seahawks finished second at 42.4 percent. Only Denver, which led the NFL in lowest completion rate (41.5 percent) on digs in 2016, was lower (41.7 percent). This may have been the last hurrah for another great secondary with Aqib Talib moving to the Rams.

Slant

The slant led to 66 touchdown passes in 2017, the most for any route.

While we know that Eli Manning threw 27 more slants than the next closest quarterback last year, New York's defense also faced the second-most slants with 62. Only the Eagles (70) faced more. They had an adventurous year on their way to finishing 13th in DVOA. The Eagles made offenses pay with five interceptions to lead the league, but the six touchdown passes they allowed were the second-most. The next-closest team in picks was Minnesota with four. The Vikings also had the best DVOA against slants in a strong tackling year from Mike Zimmer's group. The Vikings and Raiders were the only defenses to force more incompletions than completions on slants. The Titans allowed a league-high seven touchdown passes on slants.

This was another route where the Steelers (21; fewest) and Browns (26; third-fewest) faced some of the fewest totals in the league. Both were a little below average when challenged. But no one gave up the big play on a slant like the Texans. There were only five slants that gained 60-plus yards in 2017 and the Texans allowed two of them, including that weird 80-yard touchdown to T.Y. Hilton that we highlighted in Part I.

The 49ers easily had the worst DVOA against slants after allowing a league-high 76.7 percent of them to be completed. They even benefitted from two drops, but that's nowhere near the benefit that the Broncos and Panthers each received with eight slants dropped apiece.

Drag

The Patriots were tied for second in the league in drag routes faced in 2016 with 51. In 2017, Alex Smith threw eight drag routes against the Patriots in Week 1, and half of those plays produced a first down. The Patriots never saw that many drags in another game in the regular season, but still faced a league-high 55 drag routes, 17 more than the next closest team (Seattle). That's strange since it was usually a losing proposition for offenses. Only 19.1 percent of the drag routes against the Patriots after Week 1 produced a first down.

Carolina faced a league-low 12 drag routes, but all 12 were completed to give the Panthers the worst DVOA and worst YPA. Washington, No. 1 in DVOA, defended these plays well with 3.8 YPA (second behind only Pittsburgh).

Only five defenses allowed multiple touchdown passes on drag routes, but no one allowed three scores. Arizona and Atlanta were the only defenses to intercept two passes on drag routes.

Go/Fly

There could be some correlation between playing with the lead and how many go routes teams will attempt against you. Ten of the 11 teams to face at least 24 go routes in 2017 had a winning record (the Bengals did not), and seven of them were playing in the divisional round (everyone but Atlanta). The Falcons were one of four teams to face a league-low 12 go routes, but they allowed half of them to be completed. Only four of the 11 teams to face fewer than 20 go routes had a winning record.

The Ravens were tested the most with 35 go routes, but still failed to come away with an interception. The Colts actually led the league with three picks on go routes. The Broncos (five) and Raiders (four) were the only defenses to allow more than three touchdowns on go routes. In Denver's case, we are talking about five touchdowns (each of 27 yards or more) on 12 attempts, a success rate that's worth praising against a proud secondary. Remember, only about a quarter of these throws were completed last season.

Not to rain on Mike Vrabel's parade as he was hired to be the head coach of the Titans, but his 2017 Houston defense, the first for which he has ever been a coordinator at the NFL level, was not good. We know they had some huge injuries, but that secondary was roasted on several routes. The Texans were the only defense to allow more than half of their go routes to be completed (52.9 percent) and they averaged an alarming 21.6 YPA. This is one of four routes where the Texans ranked 31st or 32nd in DVOA, and we haven't even gotten to the worst one yet for them.

Carolina was impressive in allowing just 1-of-16 go routes to be completed, so why were the Eagles No. 1 in DVOA instead? The Carolina numbers include one flag for defensive pass interference. The Eagles were actually twice flagged for DPI, but only allowed two completions on 24 attempts. They also had one more interception than the Panthers and were not beaten deep for a touchdown.

Wide Receiver Screen

Let's talk déjà vu. In 2016, the Patriots faced a league-low eight wide receiver screens. Maybe it has something to do with playing the lead so much. After all, the WR screens in 2017 came with an average scoring margin of -1.5 points, the third highest among the 22 routes with at least 200 attempts. Then again, the team the 2016 Patriots played in the Super Bowl, Atlanta, faced 33 WR screens, and that defense was right behind New England in average scoring margin. Flash forward to 2017 and the Patriots again faced the fewest WR screens in the league (10). Their latest Super Bowl opponent, Philadelphia, once again faced 33 WR screens despite ranking right behind the Patriots in average scoring margin. So for some reason offenses are afraid to throw WR screens against the Patriots. Maybe it's one futile strategy that teams actually have learned to abandon against Bill Belichick.

On the flip side, offenses loved throwing WR screens against Ben McAdoo's Giants. The Giants tied for the league lead with 40 WR screens faced in 2016 and led the league in 2017 with 39. At least teams were justified to a degree as the Giants allowed 8.0 YPA on WR screens -- only five defenses allowed more than 7.0 YPA last year. The Giants have been mediocre at defending them (20th in DVOA last year, 17th this year), but they did get one of the three interceptions on a WR screen in 2017. The Eagles and Chargers had the other two. That interception can have a sizable impact on the numbers when we're only talking about 39 plays (or fewer with other teams) in a season.

Let's look at a good example of this. There were only 20 touchdown passes allowed on WR screens, and five teams allowed two each. One of those teams was Seattle, which ranked dead last in DVOA (39.4%) and YPA (10.8). That sounds just horrible, right? But the 72-yard touchdown by DeAndre Hopkins basically cemented that status for the Seahawks all by itself. Without that play, Seattle only faced 16 WR screens on the season with a DVOA of 7.9% on those plays. That still would have ranked 30th in the league, but the YPA would have dropped to 7.0 and things just wouldn't look so grotesque. That one play, as terrible as it was for the defense, really skews things for the season, but it's not like you would write that the Seahawks are going to be vulnerable against WR screens in 2018 after losing Richard Sherman and Kam Chancellor. Hell, Chancellor was the player who blew the open-field tackle on the Hopkins play.

But that one play is also why coaches are going to continue calling WR screens in the hopes that they too can catch a break. Remember, the Giants were also the team that gave up a 52-yard touchdown on third-and-33 on a WR screen by the Rams last year.

Post

The post and slant were the only routes to hit 60 touchdown passes in 2017.

We know the post route leads to some gaudy offensive numbers, including the highest DVOA in this study. However, it also led to the highest interception rate (7.7 percent) of 2017, and one defense is largely responsible for that number. No defense faced more post routes than Jacksonville's 31, but the season's best defense responded with eight interceptions, doubling up the next closest team. The Rams had four; the Bills, Chargers, and Jets were the only other defenses to intercept three post routes last season. Jalen Ramsey had three by himself to lead the Jaguars. That does a lot to explain why the Jaguars were second in DVOA, though the Rams edged them out after only allowing 6.4 YPA.

The Patriots allowed 1-of-12 post routes to be completed, but benefitted from three drops. Offenses dropped a league-high five post routes against Tampa Bay last season. The Packers, Texans, and Giants allowed the most touchdown passes with five each on post routes. Seattle faced a league-low nine post routes.

Comeback

We're onto a route where no one faced more than 20 attempts (Pittsburgh) last season.

Arizona faced a league-low six comebacks in 2016, and finished with the second-lowest total (five) in 2017. Denver saw just four of these plays, but allowed three completions. Six defenses came away with one interception each on a comeback route. The only touchdowns in the league were allowed by the Saints and Panthers (one each).

Broken Play

These are not broken plays like aborted snaps, but plays where the quarterback scrambles and the receivers break their original routes. This is backyard/sandlot football in number format.

A lack of pressure on the quarterback can certainly lead to fewer broken plays. We saw it in 2016 when the Colts faced a league-low seven of these plays with a terrible pass rush. It happened again in 2017 when Tampa Bay tied for the league lead with 11 broken plays after having the league's worst pressure rate. However, the Buccaneers were tied with Philadelphia, which had a great pass rush, so it's not as simple as that. Playing in the NFC North can certainly boost these attempts with Aaron Rodgers and Matthew Stafford, which can help explain why the Bears faced 25 broken plays. Only Oakland saw more with 26.

Perhaps the most amusing bit here is that Seattle's defense, which fortunately doesn't have to chase Russell Wilson around, had the worst DVOA on broken pass plays. Buffalo, another team that had a scrambling quarterback (Tyrod Taylor), had the best DVOA on broken pass plays.

Baltimore cleaned up with four interceptions on broken plays. The Saints (three) were the only other team with more than two picks. Carolina is used to Cam Newton extending the play on the other side of the ball, but on defense, the Panthers allowed a league-high four touchdown passes on broken plays.

Fade

I guess they don't like fades in Florida. Tampa Bay and Miami tied for the league lead with just two fades against each defense. Jacksonville and Houston were the next lowest with only six apiece. The Cowboys (26) and Patriots (22) faced the most fades. So while offenses may be ditching the WR screens against New England, they still want to try the low-percentage fades. The Patriots finished a respectable 10th in DVOA.

Oakland was the only defense to allow more completions than incompletions, but we are only talking about nine plays. Still, that led to the worst DVOA last season. The Packers were tied for the 2016 lead in touchdown passes allowed on fades with five, and they doubled up everyone in 2017 with six touchdowns allowed. Green Bay is hoping a revamped secondary and new defensive coordinator (Mike Pettine) will yield better results in 2018. At least the Packers were one of four defenses with multiple interceptions on fades. The Cardinals were the only defense with three interceptions.

Only three defenses faced a double-digit number of back-shoulder fades: the Colts (16 attempts, 10th in DVOA), Chiefs (15 attempts, 16th in DVOA), and Titans (11 attempts, 22nd in DVOA). Five defenses each had one interception on a back-shoulder fade, and the Broncos allowed a league-high four touchdown passes on that type of timing throw.

Seam

The Lions (26) and Steelers (22) were the only defenses to face more than 20 seam passes. The Cowboys only faced a league-low seven of them. This was another route where Jacksonville shined at taking the ball away. The Jaguars had four interceptions on seam routes. Six other defenses had two interceptions. The reason the Jaguars aren't any higher than eighth in DVOA is because they also allowed three touchdown passes, tied with Vikings and Patriots for the second most. The Raiders allowed a league-high four touchdown passes on seam routes.

Summary

Like we did for quarterbacks, here is the average rank for each defense in DVOA over the 12 routes.

That's not bad when the Super Bowl champions are first and the 0-16 team is last. One team that really stood out to me was Tampa Bay finishing 15th here despite having the No. 31 pass defense by DVOA. That just goes to show how the totally inept pass rush the Buccaneers had hurt their ability to cause havoc as a unit. Remember, these numbers don't include sacks.