Flexbone

The flexbone formation is an offensive formation in American football that uses a quarterback, five offensive linemen, three running backs, and varying numbers of tight ends and wide receivers. The flexbone formation is a predominant running formation derived from the wishbone formation and it features a quarterback under center with a fullback lined up directly behind the quarterback. There are two smaller running backs called slotbacks aligned behind the line of scrimmage on each side of the offensive line. The slotbacks are sometimes incorrectly referred to as wingbacks. But, in order to be a wingback, there must be a guard, tackle and tight end all on one side of the center on the line of scrimmage and then the wingback off the line of scrimmage (as featured in the unbalanced formation diagram).

Air Force Academy Head Coach Fisher DeBerry was once quoted as saying "we need to be more flexible in the Bone." Hence, the term "Flexbone" was born. The design of the formation itself, however, was not created by Fisher DeBerry. The flexbone is largely the same as the Double Slot formation that Glenn "Tiger" Ellison had created over two decades before the flexbone was born. Incidentally, the option-style running game in the flexbone is based entirely around the Cowboy and Gangster series' of Ellison's Run-and-Shoot playbook.

The basic play run from the flexbone is known as a triple option, or veer. Often the quarterback first sends one of the slotbacks in motion to the other side. While he is still in motion behind the fullback, the quarterback then receives the ball from the center. Next, the fullback (FB) either takes the football from the quarterback or 'fakes' that he has taken the football. If the fullback takes the football, then he runs straight into the line of scrimmage and attempts to gain yardage. If the fullback does not take the football, then the quarterback sprints parallel to the line of scrimmage with the motion slotback trailing him. The quarterback can either turn upfield or pitch the football to the trailing slotback. Hence the term triple because the fullback is option number one, the quarterback keeping the ball is option number two, and the quarterback pitching to the slotback is option number three. The triple option forces defenses to worry about fullbacks running in the middle of the offensive line and to worry about quarterbacks and slotbacks running to the outside of the line. The decision of who is to carry the ball (which option to make) can either be made before the play in the huddle, or during the play by the QB, who will make decisions based on the position and play of certain defensive players and what they are doing. The quarterback reads the defensive end on the side the play is going to when deciding whether to hand to the fullback or to keep it himself. If he sees the end is committed to stopping the fullback in the middle, the QB will keep it. If the end is staying back to contain the QB on the outside, he will give it to the fullback. If the quarterback does not hand to the FB, he will then read the end to see if he is committed to playing the SB on the pitch or the QB. If he is playing the QB, then he will pitch it to the slotback. If the end is committed to stopping the slotback on the pitch, the QB will take the ball upfield himself.

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