Stack

Two receivers aligned vertically (one directly behind the other) at one outside spot, with the third receiver wide on the opposite side. The stack disguises route distribution because defenders can't identify which receiver is going where pre-snap. Common designs: front receiver runs a quick out / hitch (occupies the corner) while the back receiver runs a vertical / dig / wheel (gets free release). Pairs with quick-game pick concepts and shotgun screens. Best vs man — vs zone, the stack just gives the corner an easy read. In 5v5 flag there is no back: the third receiver isolates backside while the stack pair works the strong side.