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defense / split field coverage
A split-field call that plays Cover 2 to one side and quarters to the other.
Animated assignment view
Both safeties show split depth, but corner leverage indicates a cloud side and a quarters side.
Ball at the line
How it works
The defense assigns coverage by formation side: a cloud corner and half safety protect the weak side, while a corner and safety use quarters rules to the passing strength. Underneath defenders connect the two structures.
Tailor coverage to uneven receiver distributions without rotating the entire secondary into one family.
One half of the defense plays Cover 2 and the other half plays Cover 4, giving each side a different answer to the formation.
Cover 6 requires precise seam communication because route distributions can move a receiver from one set of match rules into another after the snap.
Call structure
A standard two-high shell hides which side will play cloud technique until corner leverage becomes clear near the snap.
{
"schema": "openplay-football",
"schemaVersion": "0.1",
"id": "cover-6",
"slug": "cover-6",
"name": "Cover 6",
"side": "defense",
"category": "split-field-coverage",
"personnel": {
"id": "nickel-personnel",
"name": "Nickel",
"grouping": "4 DL, 2 LB, 3 CB, 2 S",
"positionCounts": {
"DL": 4,
"LB": 2,
"CB": 3,
"S": 2
}
},
"formation": {
"id": "even-front",
"name": "Even Front",
"family": "four-down",
"strength": "variable",
"description": "An even front supports quarters coverage to the passing strength and Cover 2 to the weak side."
},
"situationTags": [
"two-high",
"split-field",
"formation-adjustment"
],
"players": [
{
"id": "le",
"position": "DE",
"label": "E",
"initialCoordinate": {
"x": 20,
"y": 1
},
"alignment": "Left edge",
"side": "defense",
"ratingRole": "passRush"
},
{
"id": "dt",
"position": "DT",
"label": "T",
"initialCoordinate": {
"x": 24,
"y": 1
},
"alignment": "Left tackle",
"side": "defense",
"ratingRole": "passRush"
},
{
"id": "nt",
"position": "DT",
"label": "N",
"initialCoordinate": {
"x": 29,
"y": 1
},
"alignment": "Right tackle",
"side": "defense",
"ratingRole": "runDefense"
},
{
"id": "re",
"position": "DE",
"label": "E",
"initialCoordinate": {
"x": 33,
"y": 1
},
"alignment": "Right edge",
"side": "defense",
"ratingRole": "passRush"
},
{
"id": "will",
"position": "LB",
"label": "W",
"initialCoordinate": {
"x": 22,
"y": 6
},
"alignment": "Weak hook",
"side": "defense",
"ratingRole": "zoneCoverage"
},
{
"id": "mike",
"position": "LB",
"label": "M",
"initialCoordinate": {
"x": 31,
"y": 6
},
"alignment": "Strong hook",
"side": "defense",
"ratingRole": "zoneCoverage"
},
{
"id": "lcb",
"position": "CB",
"label": "C",
"initialCoordinate": {
"x": 6,
"y": 4
},
"alignment": "Weak cloud",
"side": "defense",
"ratingRole": "zoneCoverage"
},
{
"id": "nickel",
"position": "CB",
"label": "N",
"initialCoordinate": {
"x": 38,
"y": 5
},
"alignment": "Strong apex",
"side": "defense",
"ratingRole": "zoneCoverage"
},
{
"id": "rcb",
"position": "CB",
"label": "C",
"initialCoordinate": {
"x": 48,
"y": 7
},
"alignment": "Strong quarter",
"side": "defense",
"ratingRole": "zoneCoverage"
},
{
"id": "ls",
"position": "S",
"label": "S",
"initialCoordinate": {
"x": 17,
"y": 14
},
"alignment": "Weak half",
"side": "defense",
"ratingRole": "zoneCoverage"
},
{
"id": "rs",
"position": "S",
"label": "S",
"initialCoordinate": {
"x": 36,
"y": 13
},
"alignment": "Strong quarter",
"side": "defense",
"ratingRole": "zoneCoverage"
}
],
"preSnap": {
"description": "Both safeties show split depth, but corner leverage indicates a cloud side and a quarters side.",
"shifts": []
},
"assignments": [
{
"id": "weak-cloud",
"playerId": "lcb",
"type": "zone-coverage",
"zone": [
{
"x": 0,
"y": 0
},
{
"x": 13,
"y": 0
},
{
"x": 13,
"y": 10
},
{
"x": 0,
"y": 10
}
],
"responsibility": "Jam number one and protect the weak flat."
},
{
"id": "weak-half",
"playerId": "ls",
"type": "zone-coverage",
"zone": [
{
"x": 0,
"y": 10
},
{
"x": 27,
"y": 10
},
{
"x": 27,
"y": 35
},
{
"x": 0,
"y": 35
}
],
"responsibility": "Protect the weak deep half and overlap the sideline."
},
{
"id": "strong-inside-quarter",
"playerId": "rs",
"type": "zone-coverage",
"zone": [
{
"x": 27,
"y": 9
},
{
"x": 44,
"y": 9
},
{
"x": 44,
"y": 35
},
{
"x": 27,
"y": 35
}
],
"responsibility": "Match the strong-side inside vertical."
},
{
"id": "strong-outside-quarter",
"playerId": "rcb",
"type": "zone-coverage",
"zone": [
{
"x": 40,
"y": 8
},
{
"x": 53,
"y": 8
},
{
"x": 53,
"y": 35
},
{
"x": 40,
"y": 35
}
],
"responsibility": "Match the strong-side outside vertical."
},
{
"id": "strong-apex",
"playerId": "nickel",
"type": "zone-coverage",
"zone": [
{
"x": 34,
"y": 2
},
{
"x": 53,
"y": 2
},
{
"x": 53,
"y": 13
},
{
"x": 34,
"y": 13
}
],
"responsibility": "Carry number two before expanding to the strong flat."
},
{
"id": "middle-hook",
"playerId": "mike",
"type": "zone-coverage",
"zone": [
{
"x": 17,
"y": 3
},
{
"x": 37,
"y": 3
},
{
"x": 37,
"y": 14
},
{
"x": 17,
"y": 14
}
],
"responsibility": "Wall crossers and close the middle hook."
},
{
"id": "left-rush",
"playerId": "le",
"type": "pass-rush",
"path": [
{
"type": "straight",
"to": {
"x": 23,
"y": -7
}
}
],
"technique": "Contain"
},
{
"id": "inside-rush",
"playerId": "dt",
"type": "pass-rush",
"path": [
{
"type": "straight",
"to": {
"x": 26,
"y": -6
}
}
],
"technique": "B-gap"
},
{
"id": "nose-rush",
"playerId": "nt",
"type": "pass-rush",
"path": [
{
"type": "straight",
"to": {
"x": 28,
"y": -6
}
}
],
"technique": "A-gap"
},
{
"id": "right-rush",
"playerId": "re",
"type": "pass-rush",
"path": [
{
"type": "straight",
"to": {
"x": 31,
"y": -7
}
}
],
"technique": "Contain"
}
],
"timeline": [
{
"type": "pre-snap",
"atMs": 0
},
{
"type": "snap",
"atMs": 500
},
{
"type": "assignment-start",
"atMs": 550,
"playerId": "nickel"
},
{
"type": "play-end",
"atMs": 4500
}
],
"narrative": {
"summary": "A split-field call that plays Cover 2 to one side and quarters to the other.",
"fullExplanation": "The defense assigns coverage by formation side: a cloud corner and half safety protect the weak side, while a corner and safety use quarters rules to the passing strength. Underneath defenders connect the two structures.",
"strategicPurpose": "Tailor coverage to uneven receiver distributions without rotating the entire secondary into one family.",
"idealSituations": [
"Trips formations",
"Field-boundary situations",
"Against a featured strong-side receiver"
],
"strengths": [
"Formation-specific leverage",
"Strong vertical control",
"Cloud support to the weak side"
],
"weaknesses": [
"Communication at the middle seam",
"Runs toward the quarters safety",
"Crossers moving between coverage families"
],
"keyRead": "Each side keys its local receiver distribution while the middle hook defender handles routes crossing between the two families.",
"watchFor": [
"Different corner techniques on each side",
"The strong safety matching number two",
"Crossers entering the opposite coverage"
],
"beginnerExplanation": "One half of the defense plays Cover 2 and the other half plays Cover 4, giving each side a different answer to the formation.",
"advancedNote": "Cover 6 requires precise seam communication because route distributions can move a receiver from one set of match rules into another after the snap."
},
"simulation": {
"difficulty": "advanced",
"conceptTags": [
"zone-coverage",
"cover-six",
"split-field"
],
"baseSuccessRate": 0.61,
"yardRange": {
"min": -9,
"max": 40
},
"turnoverRisk": 0.041
},
"defensiveStructure": {
"front": "Even four-down front",
"personnel": "Nickel 4-2-5",
"coverage": "Cover 6 split-field",
"rushPlan": "Rush four and use asymmetric coverage leverage to delay the quarterback's full-field progression.",
"runFits": [
"Quarters safety reads run-pass",
"Cloud corner forces weak-side runs",
"Linebackers fit interior gaps",
"Ends retain contain"
],
"disguise": "A standard two-high shell hides which side will play cloud technique until corner leverage becomes clear near the snap.",
"strengths": [
"Trips adjustment",
"Split-field flexibility",
"Vertical leverage"
],
"weaknesses": [
"Cross-field routes",
"Quarters-side run support conflict",
"Complex communication"
],
"idealSituations": [
"Trips formations",
"Field-side passing tendency",
"Second and long"
],
"vulnerableConcepts": [
"mesh",
"outside-zone",
"play-action-cross"
]
}
}