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Learn how to identify defensive coverages instantly using the 'Box vs. Triangle' rule in this MatchQuarters film breakdown of the Seattle Seahawks defense against the San Francisco 49ers. This study decodes Mike Macdonald's scheme against Kyle Shanahan, teaching you how to read cornerback leverage and front structure to predict Cover 2 and Quarters before the snap.
» In this episode:
The “Box vs. Triangle” Rule: Learn how to instantly distinguish between Quarters (Box) and Cover 2 (Triangle) by looking at the geometry of the secondary.
The Cornerback “Cheat Code”: Discover why the cornerback never lies—if he stays high, it’s Quarters; if he squats low in a trail technique, it’s Cover 2.
Decoding Front Structures: Understand the difference between “Wide 9” and “G Fronts” (2i technique) and how they dictate the defensive run fits.
Defending the “Dirty Bunch”: See how the Seahawks adjust their coverage rules to handle the 49ers’ compressed “Dirty Bunch” formations and “Nub” tight ends.
Advanced Coverage Layers: A breakdown of “Cover 8” (Quarter-Quarter-Half) and how Mike Macdonald mixes coverages to cap vertical routes while protecting the flats.
Timestamps:
00:00 - Intro: The Secret Geometry of Defense
00:33 - Learning to Watch Film
01:09 - Step 1: Identifying Front Structure & Formations
02:16 - Personnel Math: How to Identify 21 Personnel
03:29 - The Too High Shell & Setting the Field or Boundary
05:58 - The Cheat Code: Low Corner vs. High Corner
06:23 - Defining Cover 8 - Quarter Quarter Half
07:05 - The Geometry of Defense: The Triangle vs. The Box
09:36 - Tech Stunts & Natural Pass Rush Games
10:29 - End Zone View: Wide 9 & G Fronts - 2i Technique
13:03 - Defending the Dirty Bunch & Condensed Sets
15:09 - Match Quarters Rules - The Lock Call
16:59 - 3rd Down Strategy: Dime Packages & Motion Adjustments
19:09 - What is Match Quarters? Man with Rules
22:38 - The Wide Front or Jet Front & Protection Manipulation
24:14 - The Nub Tight End & Setting Front Strength
26:40 - Split Field Coverage Layers - Cloud vs. Quarters
29:23 - Mid Zone Run Fits & Cutback Lanes
31:26 - Analyzing the Crack Toss vs. Wide 9
34:56 - The Pinch Front or 6-1 Look & 4th Down Stops
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» Other resources:
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