Cover 1

In Cover 1 (often called Man-Free), cornerbacks and coverage linebackers lock onto eligible receivers in man-to-man coverage while one free safety patrols the deep middle third. Because the post safety protects against deep vertical routes, underneath defenders play inside-trail leverage, aggressively contesting out-breaking routes and funneling vertical routes toward deep safety help.

Underneath coverage rules vary based on how many rushers the defense sends:

Rat / Hole

A four-man rush leaves an underneath linebacker or safety free to patrol the shallow middle (the hole) and undercut crossing routes.

Robber

A safety drives down from depth into the intermediate middle to intercept in-breaking dig and crossing routes.

Blitz (Cover 1 Dog)

Bringing five or six rushers leaves zero underneath zone help, putting all five eligible receivers in isolated man coverage.