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» Week 4 DVOA Ratings

Five different teams from last year's DVOA top eight rank in the bottom half of the league through four weeks of 2014. What can we learn from other teams with similar starts in the past?

02 Nov 2012

Under Pressure: Unblocked Sacks

by J.J. Cooper

The biggest mantra of Under Pressure is the idea that not all sacks are created equal.

There are a lot of different ways to break down sacks. You can look at how fast the sack occurred, how many rushers were needed to generate the sack, or how effectively the offensive line blocked.

But on any given play, the defensive coordinator’s biggest goal is to get a rusher a free run at the quarterback. In counting up the unblocked sacks this season, it’s clear that defensive coordinators are having way too easy of a time getting an unblocked rusher free against the Eagles.

The Eagles have given up a sack to an unblocked rusher on 2.45 percent of all their dropbacks this season. (That's seven total sacks.) No other team has come close to matching that number of unblocked sacks. More than a third of all Eagles sacks this season have come when a rusher came untouched.

It would appear the blame could be spread equally between quarterback Michael Vick, the play calling, and the offensive line. Vick has struggled to recognize defensive backs blitzing. Very few protection schemes try to account for cornerback blitzes -- it's usually the responsibility of the quarterback and the receivers to recognize them and take advantage of the holes in the secondary created by them. Safety blitzes are also often left to the responsibility of hot routes, as a safety coming off the edge is often impossible to block by scheme.

In Vick’s case, he’s been sacked by an unblocked defensive back three times this season. One glaring example was a poorly disguised blitz by Cardinals safety Kerry Rhodes in Week 3. On a third-and-goal, Rhodes was quite clearly coming in the pre-snap read, but Vick didn’t see him and was sacked for a six-yard loss, then fumbled the ball, allowing Arizona's James Sanders to return it for a touchdown.

But it’s not been all Vick’s fault. The Eagles have also managed to twice give up sacks where a linebacker on an X-blitz (where two linebackers hit the same gap) came completely unblocked. The Eagles have slanted the line the wrong way against an overload blitz, giving a linebacker a free run at the quarterback. On one play, Danny Watkins appeared to block the wrong man, which allowed Steelers linebacker Jason Worilds an extremely easy sack.

Unblocked Sacks, through Week 8
Team Sacks Allowed Percent Team Sacks Percent
PHI 7 2.45% ATL 5 2.05%
ARI 5 1.44% MIA 5 1.52%
SEA 4 1.41% HOU 4 1.49%
STL 4 1.41% DEN 4 1.47%
NYJ 4 1.36% DAL 3 1.44%
MIA 3 1.27% STL 4 1.30%
NO 4 1.22% PIT 3 1.27%
WAS 3 1.09% BAL 3 1.14%
MIN 3 1.07% NYJ 3 1.11%
IND 3 0.98% ARI 3 1.09%
TEN 2 0.89% SF 3 1.05%
Team Sacks Allowed Percent Team Sacks Percent
HOU 2 0.85% NYG 3 0.99%
DEN 2 0.75% GB 3 0.91%
BAL 2 0.73% KC 2 0.89%
SD 2 0.71% IND 2 0.88%
KC 2 0.68% DET 2 0.79%
GB 2 0.61% NO 2 0.78%
DET 2 0.59% PHI 2 0.76%
BUF 1 0.44% TB 2 0.72%
CAR 1 0.43% NE 2 0.65%
CHI 1 0.41% MIN 2 0.62%
TB 1 0.41% WAS 2 0.58%
Team Sacks Allowed Percent Team Sacks Percent
JAC 1 0.40% CIN 1 0.40%
CIN 1 0.38% OAK 1 0.38%
ATL 1 0.36% JAC 1 0.37%
PIT 1 0.35% SD 1 0.33%
NYG 1 0.33% SEA 1 0.31%
CLE 1 0.32% BUF 0 0.00%
NE 1 0.30% CAR 0 0.00%
DAL 0 0.00% CHI 0 0.00%
OAK 0 0.00% CLE 0 0.00%
SF 0 0.00% TEN 0 0.00%

Flipping it around to look at which defensive coordinators are managing to get a rusher free, it’s impressive to see what the Falcons and Dolphins are managing to do. While the gap between the top teams in generating unblocked sacks and the middle of the pack is not nearly as pronounced, both Atlanta and Miami have managed to pick up five sacks due to a rusher coming untouched.

The Falcons are quite willing to blitz defensive backs in a variety of situations, as was evident this week when safety Thomas DeCoud lined up as a deep safety for what appeared to be a Cover-2 alignment. At the snap he took off on a blitz, even though he was 15 yards from the line of scrimmage. Vick didn’t really recognize DeCoud’s blitz until it was too late, as DeCoud was able to surprise Vick and force him to tuck and run. DeCoud then ran him down for a two yard loss on third-and-11.

MISSED OPPORTUNITY

When a defense sends a seven-man rush, it’s often a race between the rush and the receivers. Can the rush get there before a receiver gets open?

In the Vikings-Buccaneers game last Thursday, the Bucs won the race, sacking Christian Ponder for a 10-yard loss on first-and-10 in the third quarter ... but they came perilously close to giving up a game-changing big play.

At the snap, tight end Kyle Rudolph was tasked with getting open over the middle. Defensive end Daniel Te'o-Nesheim was supposed to give him a jam and then run with him downfield, with a safety over the top to help out. Asking Te'o-Nesheim to cover Rudolph is a mismatch in any situation, but here the Bucs were gambling that one of seven rushers would get to Ponder before Rudolph could take advantage.

They shouldn’t have gotten away with it: Rudolph got an outstanding release, as he threw Te'o-Nesheim to the ground.


With all three linebackers and a defensive back blitzing, there was no one in the middle of the field to help Te'o-Nesheim out. Rudolph was open by roughly 10 yards, waving his arm frantically for what would have been a big gain.

But the gamble paid off. With only three receivers going out into the pattern, Rudolph was Ponder’s second progression. He checked the receiver to his right first, then shifted his eyes to Rudolph. By that time, linebacker Mason Foster was two steps away from lighting Ponder up. Ponder decided that discretion was the better part of bruising, so he tucked the ball away for a sack.

QUICK SACK OF THE WEEK

Last week Under Pressure showed how a pre-snap shift can cause havoc for an offensive line. We saw another example of this in that same Bucs-Vikings game.

Bucs defensive end Te'o-Nesheim lined up head up on left tackle Matt Kalil (this is called a five-technique), with defensive tackle Gary Gibson lined up to his left in the center-guard gap (a one-technique).

But just before the snap, Gibson shifted to his left, head up over the center (a zero-technique) while Teo’-Nesheim slid to his left into the guard-tackle gap (a four-technique).

The shift managed to create some confusion for the Vikings’ line. Guard Charlie Johnson stayed with Gibson while Kalil was left baffled -- he didn’t block anyone. That confusion gave Te'o-Nesheim the easiest sack he’ll ever get in the NFL -- and also only the second sack of his three-year NFL career.

Te'o-Nesheim hit Ponder just 1.4 seconds after the snap. Ponder never had a chance, and it was all because of a quick shift.

LONG SACK OF THE WEEK

Unlike the short sack of the week, there wasn’t much notable about the long sack this week. Dolphins quarterback Matt Moore had plenty of time, but when no one was open, he took off towards the sideline. After 6.8 seconds, Jets linebacker Bryan Thomas ran him down a yard behind the line of scrimmage.

Posted by: J.J. Cooper on 02 Nov 2012

2 comments, Last at 04 Nov 2012, 4:57pm by Sifter

Comments

1
by Insancipitory :: Fri, 11/02/2012 - 3:18pm

I don't know if I would agree I'd say no other team is close. There've been a few Russell Wilson "F U, I'm magic" plays that would have put the Seahawks in contention.

2
by Sifter :: Sun, 11/04/2012 - 4:57pm

Some interesting numbers, and not good ones for my beloved Eagles...

Also, just wondering if for the long sack section you could look at the longest sack where the QB is still in the pocket. Seems every week the longest sack is a guy tackled just a couple of yards behind the line over near the sideline. Maybe an awful sack formula of: yards lost + time taken.