also: bubble · quick screen
A quick throw out to a slot receiver who bubbles backward and outward, with the receivers outside him blocking. The fastest way to make a defense pay for not covering down.
A slot receiver takes a path back and outward, hence bubble, and catches a quick throw almost immediately. The receivers outside him block the defenders over them, and he runs to whatever grass those blocks create.
Its real function is arithmetic rather than yardage. If a defense has not put enough defenders out over the receivers, the bubble is an immediate profit, and if it has, the defense has taken bodies out of the box and the run game gets easier. That is why bubble is so often attached to a run play as an option rather than called on its own.
bubble, quick screentunnel screen, screen, RPOBubble is very often the pass half of an RPO rather than a called play, which means a coach hearing it may be describing a full play or one branch of another one.
Among the highest-value plays available at youth level, because youth defenses frequently do not cover down at all and the throw is short enough for almost any quarterback.