Film analysis

Having enjoyed so many discussions about the strategies of the game with many of you, I'm hoping to provide some break down of plays over the course of the season and this thread can be a quick reference guide to the vocabulary and strategies that will be mentioned in the post game All22 cut up threads.

It may take awhile coming together. I'm hoping it can be a cliff notes type of thread to all the coverages and concepts used by the 49ers and against the 49ers. It's not about players in this thread as much as Xs & Os.

All input is welcome. I'll bump the thread as I add chunks of content.

Table of Contents
Defensive Overview and Cornerback techniques - - - Post #3
MoFC versus MoFO - - - Post #4
Cover 0 - - - Post #5
Cover 1/ Cover 1 Robber - - - Post #6
Cover 2 Man - - - Post #7
Cover 2 Zone - - - Post #8
Tampa 2 - - - Post #9
Cover 3 - - - Post #10
Cover 4 - - - Post #11
Quarters coverage - - - Post #12
Cover 6 - - - Post #13
Pattern Matching - - - Post #14

Vertical Stretches - - - Post #16
Horizontal Stretches - - - Post #17
Triangle Stretch - - - Post #18
Man Coverage Busters - - - Post #19
AR Concept - - - Post #20
Packaged Plays - - - Post #21
Offensive Line Gaps & Personnel Groupings - - - Post #22
Power Blocking Run Scheme - - - Post #23
Zone Blocking Run Scheme - - - Post #24


Game Film Analysis:
Week 1 (at DAL) - - - Post #75 and on
Week 2 (vs CHI) - - - link
Week 3 (at ARI) - - - link
Week 4 (vs PHI) - - - link
Week 5 (vs KC) - - - link
Week 6 (at STL) - - - link
Week 7 (at DEN) - - - link
Week 9 (vs STL) - - - link
Week 10 (at NO) - - - link
Week 11 (at NYG) - - - link
Week 12 (vs WAS) - - - link
Week 13 (vs SEA) - - - link
Week 14 (@ OAK) - - - link
Week 15 (@ SEA) - - - link
Week 16 (vs SD) - - - link
Week 17 (vs ARI) - - - link

DEFENSE

Man Coverage: Cover 0, Cover 1, Cover 2 Man
On any given play, an offense can send out a maximum of 5 route runners. If a defense decides to play man coverage, five defenders are assigned to each eligible receiver. Assuming a standard four man pass rush, this allows the defense to have two 'free' defenders to be utilized in any way the defensive coordinator chooses: blitz, double team a WR, play zone, etc.

Zone Coverage: Cover 2 Zone, Tampa 2, Cover 3, Cover 4
The field is usually divided up into 6 underneath zones - flat, curl, hook, hook, curl, flat. Generally, the 'Out' zones in the diagram shown below are defended by the Curl/Flat defender, or the Hook/Curl defender. The deep zones are divided into halves, thirds, or fourths depending on the number of deep zone defenders assigned by the coverage call.



Cornerback Techniques
When in man coverage, CBs have various ways to cover the WR. Leverage is used to describe the positioning that the CB has on the WR. The CB's leverage, or position, can determine which routes will win or be defeated.

A CB is either 'over the top' or 'trailing' the WR. A CB can also have inside or outside leverage. Over the top would help the CB defend vertical routes. Trailing would help versus crossing routes and with the aid of safety help, can help bracket a WR.
Inside leverage would help defend against inward breaking routes, opposite goes for outside leverage.

#1
Press, Bump and Run is used to throw off timing routes by making the WR take longer to start his route, thus throwing off the timing with the QB's dropback. A failed bump can result in immediate separation gained by the WR.

Here, the CB aligns with an outside shade on the WR. The CB's outside foot is closer to the sideline compared to the WR's outside foot.


Trying to win outside leverage.




Outside leverage will help funnel the WR towards the middle of the field. Trail position because the CB has the safety to cover over the top. The CB properly uses his safety help.


The WR still tries to break his route to the outside, but is defeated because the CB has outside leverage.


#2
Press, Mirror technique is used to impede the WR's path, where ever he tries to go.


No bump (jam). Since the WR has lined up close to the sideline, the CB takes inside leverage in order to use the sideline as an additional defender (on the outside).


When mirroring a WR, the CB needs to stay in front of the WR. Basically be in his face. A CB in this position (below) can start to edge the WR closer to the sideline.




#3
Bail Technique is used to stay over the top of the WR and defeat any vertical route while keeping a CB's eyes on the QB to react to any throws. It leaves the CB vulnerable to comeback, In, and Out routes.




Vertical route defeated.


#4
Playing with a cushion will place the CB 5-7 yards off the line of scrimmage. He gets the benefits of reading run/pass and looking at the QB. Playing with a cushion leaves the CB vulnerable to short routes and pump fakes, because he's watching the QB.

Here, the CB takes a big 7 yard cushion since the ball is on the far has mark and the WR is aligned outside the numbers (far).


With his eyes on the QB, CB reads the 5 step drop. Once the QB opens his shoulder to start his throwing motion, the CB drives on the route.

Middle of Field Open vs Middle of Field Closed

When attacking vertically downfield, a QB and the WRs must make the post snap read of MoFO or MoFC. This will determine where the seams in the coverage are. Many vertical routes will change post snap depending upon where the safeties are defending in order to have the WR run into the seams.

Middle Of the Field Open (MOFO) describes a coverage shell (deep zone defenders) where there is a seam down the center of the field. It is the area between the deep zone defenders. This is cover2 and cover4 where the middle of the field has a seam.



Middle Of the Field Closed (MOFC) describes a coverage shell (deep zone defenders) where the middle of the field has a defender, and there is no seam down the very center of the field. This is cover1 and cover3 where there is a defender patrolling the middle of the field.

Cover 0 (Middle of Field Open)

Strengths:
- Can send heavy pressure with 6 or more pass rushers
- Defend inside run

Weaknesses:
- No safety help
- Run support at second level
- If CBs are playing with a cushion: no underneath help on crossing routes, slants
- If CBs playing press: no over the top help


Man coverage all around with no safety help. If a defender is assigned to a WR in the backfield, and that WR stays in to pass block, then that defender is free to blitz. Here, the CBs play with a cushion on the outside WRs.

Cover1 (Middle of Field Closed)

Strengths:
- Can send 5 or more pass rushers
- Safety help in deep middle

Weaknesses:
- No safety help towards sidelines
- If CBs are playing with a cushion: no underneath help on crossing routes
- If CBs playing press: no over the top help on wideouts, poor run support from CBs

Cover 1: Extra defender is used to double cover one of the slot WRs.


Man coverage with one deep safety




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Cover 1 Robber
A variation of Cover 1 where the extra defender will play the hook zones to take away the short middle area of the field. Most times, the robber will be one of the safeties coming downhill to 'rob' the middle of the field.

Cover 2 Man (Middle of Field Open)

Strengths:
- One or both safeties can be used to double cover a WR
- CBs can aggressively press WRs, knowing there is help over the top from 2 deep safeties

Weaknesses:
- Poor run support: 7 in the box, safeties aligned deep (over 15 yards)
- Large seam in between the two deep safeties
- Hard to disguise versus pre-snap motion

Cover 2 Zone (Middle of Field Open)

Strengths:
- 5 underneath zone defenders
- CBs can aggressively press WRs

Weaknesses:
- Only two deep zone defenders
- Large seam down the middle of field, between safeties

Tampa 2 (Middle of Field Closed)
This coverage tries to get the best of both worlds from Cover 2 Zone and Cover 3. (The 49ers do not call this coverage so I have to use an opponent's defense.)

Strengths:
- CBs can aggressively press WRs
- Strong in the flats
- 3 deep zone defenders

Weaknesses:
- Middle linebacker assigned to cover a deep zone
- Soft coverage of Hook zones

Cover 3 (Middle of Field Closed)

Strengths:
- 3 deep zone defenders
- Run defense with 8 in the box

Weaknesses:
- Only 4 underneath zone defenders
- Cannot press wideouts because CBs need to bail to their deep third zone

Cover 4 (Middle of Field Open)

Primarily used in long down and distances, but not quite a prevent defense. Example below is 3rd and 19.

Strengths:
- Four deep zone defenders to prevent deep pass

Weaknesses:
- Only three underneath zone defenders

Quarters (MoF Open)

Quarters is a variation of cover4. It is not a prevent defense although it is in the Cover 4 family. The biggest difference between the prevent version of cover4 and Quarters is that the Safeties are aligned under 15 yards off the line of scrimmage when playing Quarters (not deep). This allows the safeties to be in a better position to support the run defense since there is only 7 in the box. Using pattern matching, Quarters allows the defense to play differently on each side of the field to help in confusing the QB. Each safety is responsible for making the pre-snap call on his respective side of the field. There are lots of articles on Quarters, which explain the various ways it can be played. This article touches on the many ways Quarters can be played.

The 49ers do not play Quarters on both sides of the field (I couldn't find any examples), but they do play split coverages where one side of the field is playing Quarters. Focusing on half of the field that is playing Quarters...

Strengths:
- Possible 4 deep zone defenders
- Run defense with a possible 9 in the box (front 7 + 2 safeties)
- Can play split coverages ; different calls on each side of field
- Ability to double cover WRs

Weaknesses:
- Susceptible to out 6-8 yard out routes
- Only 3 underneath zone defenders
- Play action can get safeties to bite


(When pattern matching, WRs are numbered from the outside in. Most outside WR is #1, next one (slot) in is #2, etc.)
First, a simple read for the DBs playing Quarters (bottom of screen), where both #1 and #2 go vertical.




Both DBs match #1 and #2 vertical routes


Cover 4 "Cut" - Focusing on the Quarters side (top of screen)


#2 stays in to pass block, both DBs playing Quarters turn their attention to #1. The safety must be flat footed as he reads #1, do not gain depth.


CB plays over the top to allow safety to drive downhill on any inside route by #1.


Pass to #1 is defended.


Quarters (supporting the run)
With only 7 in the box, the safety(s) playing Quarters are asked to aggressively support in run defense once he reads #2 is run blocking.

Cover 6 (Middle of Field Open)
Cover 6 is simply cover 2 + cover 4 (Quarters) where one side of the field plays cover2 and the other side plays cover 4. It tries to confuse the QB by playing split coverage. Cover 6 is also called "quarter-quarter-half" due to how the deep zones are divided.

Cover 6 can be identified by the depth at which the two safeties are playing. The safety playing Quarters will align 10-15 yards off the line of scrimmage. The safety playing cover 2 will align deeper and gain depth at the snap. This is because the cover2 safety is responsible for an entire deep 1/2 zone. Most times, the placement of the ball on the hash marks is what determines which side of the field plays cover 2 and which plays Quarters. Since the safety playing deep 1/2 has a lot of room to cover, he is protected given the short side of the field (determined by ball on hash mark). The wide side of the field will play Quarters since there are two DBs, each covering deep 1/4.

All the examples for Quarters (above) have the 49ers playing Cover 6.

Notice where the ball is placed on hash mark. The short side of the field is playing cover2 man. The wide side of the field is playing Quarters while they pattern match underneath.


Cover 2 man is easy to see (top of screen). Quarters side is making their reads.

Pattern Matching underneath: The slot defender making the 'Under!' call alerts the defender on the other side of the formation that a crossing route is coming into his area. If the slot defender were to follow the slot WR, he would get picked (rub route).


Pattern matched underneath.


Because #2 went inside, the safety playing Quarters can double up on #1. #1 goes vertical and is bracketed.


Cover 6: cover 2 man + Quarters (cover 4 Cut)


QB took snap and first looked to his right, saw Cover 2 man. Then looks to his left.
Cover 2 side: CBs in man coverage. Safety gains depth to cover his deep 1/2.
Quarters side: #2 goes outside, safety turns attention to #1.


Cover 4 Cut. The safety cuts the In route from #1.
- Double moves can confuse pattern matching: #2 used a double move , Out and Up. When the safety read that #2 went out, he jumps #1. Then #2 went Up to attack the area the safety vacated.

Pattern Matching

Pattern Matching is a concept that allows the defender in the best position on the field to cover the WR that enters that defender's zone. All Pattern Matching starts off as zone coverage. The defense relies on the premise that all WR routes will be distributed around the field. No two routes will be next to one another as the play unfolds. Defenders that are Pattern Matching do not know who they will be covering pre-snap. They just know the general area on the field that they will be defending. Once the WRs make the break in their route, that is when the defenders sort out who is covering who. At that point, it becomes man coverage.

Any defense using Pattern Matching will have its own set of rules that the defenders follow. These rules depend on the coverage being called, which depends on the tendencies of the offense when the offense is scouted.

WRs are numbered starting from the outside, then to the center of the field (ball). Same numbering system is applied to the other side of the field. This aids the defenders in applying the rules of Pattern Matching.

Strengths:
- Less seams exposed creating tighter windows to throw into
- Plays to the leverage of the defenders, giving the defenders an advantage
- Effective against rub routes, bunch formations

Weaknesses:
- Double moves can confuse pattern matching rules
- Pre-snap motion/shifting can cause confusion regarding coverage assignments
- Harder to teach on a team wide scale

Cover 6 Pattern Match versus the Mesh Concept (man coverage buster)


The two defenders in the middle of the field do not follow on a short crossing route. Instead, they make the 'Under' call. Verbiage will vary depending on the team, but the meaning is the same. It alerts the defender on the other side of the formation that a WR is coming into their zone.


The Mesh concept being ran does not produce a pick on the defenders because the defenders did not follow them across the middle of the field. Once the WRs cross one another, the defenders match up in man coverage.


When running the Mesh concept (man coverage buster), WRs are taught to sit down in a soft spot if it's zone coverage. Once they sit down, the Pattern Matching defense morphs to man coverage and there is no soft spot to sit down in. Pattern Matching defeats a man coverage busting concept (Mesh concept).


Cover 6 Pattern Match versus the Smash concept (zone coverage buster)

The rules detailed below are common and are my best guess.






Pattern Matching defeats a zone busting concept.

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