Gap responsibility
Every defender owns a gap
The spaces between offensive linemen are lettered (A-gap between center and guard, B between guard and tackle, and so on), and every defender is responsible for one. If everyone owns their gap, there's nowhere to run.
When it applies
The foundation of every run defense, every snap.
+ StrengthsSound structure — no free lanes when everyone does their job.
− Trade-offsOne busted fit and the back is in the secondary; requires total discipline.
Filed under: Run fits and gap control