Flood
Three-level route overload to one side of the field
- Read #1
- Reads 2+
- Checkdown
- Telestrator
Flood is a three-level passing concept that overloads one side of the field with routes at different depths, typically a flat, a curl or out at the intermediate level, and a deep out or corner route. The beauty of Flood is its simplicity: it puts three receivers against two defenders, guaranteeing someone comes open. Bill Walsh popularized the concept within his West Coast offense, and it has become a cornerstone play for trips formations. The concept is especially effective against Cover 3, where three vertical zones leave the flats vulnerable to horizontal stretching.
Reads
5 ROUTESTap a route to trace it on the field.
Read progression
Read deep to short on the flood side: look for the corner route first, check the out underneath, then dump to the flat. If the defense overrotates, come back to the dig or check down.
Why it works
By placing three receivers at three different levels on one side, Flood creates a numerical advantage against zone coverage. The flat defender and deep outside defender must account for three threats with only two bodies, guaranteeing an open window at one of the three levels.
Conflict defender
The flat defender, alone against TWO receivers at different depths after the go route removes the deep CB
Play-action pairings
- Outside Zone · QB fakes zone handoff and boots opposite (bootleg/naked)
Origin
Sid Gillman pioneered the three-level vertical stretch concept.
Flood vs coverages
13 RATED- Cover 3Beats it
Three receivers attack two defenders (flat and deep-third CB) on one side, creating a 3-on-2 advantage that floods the zone.Show reasoning
Conflict defender. Flat defender (rolled-down SS, curl/flat zone)
Why the offense wins. Three receivers attack two defenders (flat and deep-third CB) on one side, creating a 3-on-2 advantage that floods the zone.
Key adjustment. Roll the safety to the flood side and play robber underneath.
- Cover 6Edge
Flood to the boundary Cover 2 side creates the same 3-on-2 stretch you'd see vs base Cover 2.Show reasoning
Conflict defender. Flat defender
Why the offense wins. Flood to the boundary Cover 2 side creates the same 3-on-2 stretch you'd see vs base Cover 2.
Why the defense wins. Run into the quarters side, the corner carries the corner route as #1 vertical and the safety drives the out off #2, so the stretch is matched by rule.
Key adjustment. Check the quarters half to the flood side; the pattern-match rules cover all three levels.
- Tampa 2Edge
Flood's 3-on-2 vertical stretch still works vs the deep-half safeties, the corner sits between flat CB and deep half.Show reasoning
Conflict defender. Flat cornerback
Why the offense wins. Flood's 3-on-2 vertical stretch still works vs the deep-half safeties, the corner sits between flat CB and deep half.
Why the defense wins. Tampa 2 has 4 underneath defenders + the MIKE drop, the flood can be squeezed if the LB carries vertically.
Key adjustment. Reroute the seam at the line and have the MIKE carry it.
- Cover 3 MatchEdge
Match rules send the SS with the out as #2 and the corner with the corner route, so the flat from the back is open until the hook defender expands; the out still has the SS trailing from inside.Show reasoning
Conflict defender. Flat defender (SS matching #2 vertical)
Why the offense wins. Match rules send the SS with the out as #2 and the corner with the corner route, so the flat from the back is open until the hook defender expands; the out still has the SS trailing from inside.
Why the defense wins. Three defenders match three routes by rule; if the SS carries the out and the hook defender rallies to the flat, the only throw is the out in a tight window.
Key adjustment. Have the SS match the out, the corner carry the corner route and the hook linebacker expand to the flat on his rule.
- Cover 2Toss-up
Cornerback can sink to bracket the out while the safety covers the deep route.Show reasoning
Conflict defender. Deep-half safety (flood side)
Why the offense wins. The out route can sit underneath the deep-half safety in the flat.
Why the defense wins. Cornerback can sink to bracket the out while the safety covers the deep route.
Key adjustment. Have the corner sink under the out while the half safety stays on top of the corner route.
- Cover 4Toss-up
Quarters read allows the CB to pass off the flat and stay on top of the corner.Show reasoning
Conflict defender. Cornerback (quarters zone)
Why the offense wins. The corner route can find a window between the CB and safety if the flat route holds the CB.
Why the defense wins. Quarters read allows the CB to pass off the flat and stay on top of the corner.
Key adjustment. Have the corner pass the flat to the SAM and stay on top of the corner route; the safety reads #2's out.
- RobberToss-up
The intermediate sail can be picked off by the robber on a misread.Show reasoning
Conflict defender. Flat defender
Why the offense wins. The flat and corner routes stay perimeter and outside the robber.
Why the defense wins. The intermediate sail can be picked off by the robber on a misread.
Key adjustment. Keep the robber at the out's depth; the man defenders take the flat and the corner route outside him.
- BracketToss-up
If a flood receiver is bracketed, the numbers advantage drops to 2-on-2.Show reasoning
Conflict defender. Flat defender
Why the offense wins. Flood's 3-on-2 still works if the bracket is on the X (not the flood receivers).
Why the defense wins. If a flood receiver is bracketed, the numbers advantage drops to 2-on-2.
Key adjustment. Set the bracket on a flood receiver so the three-level stretch drops to two-on-two.
- Cover 3 CloudToss-up
The cloud rotation puts the SS in the deep middle and lets the SAM play the curl/flat with inside help; into the cloud, the squat corner takes the flat and the rotated safety caps the corner route, which leaves only the out.Show reasoning
Conflict defender. Curl/flat defender (SAM, away from the cloud)
Why the offense wins. Away from the cloud, the right side still has a deep-third corner and one curl/flat defender against three levels; the out and the flat put the SAM in a bind.
Why the defense wins. The cloud rotation puts the SS in the deep middle and lets the SAM play the curl/flat with inside help; into the cloud, the squat corner takes the flat and the rotated safety caps the corner route, which leaves only the out.
Key adjustment. Roll the cloud to the flood side so the squat corner takes the flat and the safety behind him takes the corner route.
- Cover 1Tough
Man coverage matches all three flood levels with dedicated defenders; no zone conflict to exploit.Show reasoning
Conflict defender. Flat defender (underneath man/zone)
Why the defense wins. Man coverage matches all three flood levels with dedicated defenders; no zone conflict to exploit.
Key adjustment. Match all three levels man-for-man and let the FS lean to the flood side.
- Cover 2 ManTough
Two-deep safeties and man underneath cover the three-level Flood read, the corner route is bracketed.Show reasoning
Conflict defender. Flat defender
Why the offense wins. The flat route can win against a LB matched on the back.
Why the defense wins. Two-deep safeties and man underneath cover the three-level Flood read, the corner route is bracketed.
Key adjustment. Press the outside receivers and let the LB on the back run the flat down; the half safeties cap the corner route.
- Palms / ClampTough
With #1 vertical, the corner carries the clear-out man-for-man, the safety drives down on the sail off his #2 key, and the OLB widens with the flat — all three levels matched by rule.Show reasoning
Conflict defender. Palms-side cornerback
Why the offense wins. The flat route is unaffected by Palms triggers.
Why the defense wins. With #1 vertical, the corner carries the clear-out man-for-man, the safety drives down on the sail off his #2 key, and the OLB widens with the flat — all three levels matched by rule.
Key adjustment. Have the corner carry #1 vertical, the safety drive the out off #2, and the OLB widen with the flat.
- Cover 0Avoid
Zero blitz arrives faster than the three-level read can develop; man defenders match all levels.Show reasoning
Conflict defender. MIKE linebacker (man on #3 or sixth rusher)
Why the defense wins. Zero blitz arrives faster than the three-level read can develop; man defenders match all levels.
Key adjustment. Bring six and match the three levels man-for-man; the read never develops.