I Formation - Common Variations

Common Variations

Many subtypes of the I formation exist, generally emphasizing the running or passing strengths of the base version.

• The Big I places a tight end on each side of the offensive line (removing a wide receiver). Coupled with the fullback's blocking, this allows two additional blockers for a run in either direction. This is a running-emphasis variant.
• The Power I replaces one wide receiver with a third back (fullback or running back) in the backfield, set up to one side of the fullback. This is a running-emphasis variant.
• The Jumbo or Goal-line formation further extends the Power I or Big I, adding a second tight end and/or third tackle to the line, respectively. This variant has no wide receivers and is all but exclusively a running formation intended to reliably gain minimal yardage, most commonly two yards or less.
• The Three-wide I replaces the tight end with a third wide receiver. This is a passing-emphasis variant.
• The Maryland I (also known as the Stack I) is similar to the Power I except that instead of placing the third back to one side of the fullback, the fullback, third back, and tailback line up directly in front of each other (hence the term “Stack”). Obviously, this is a running-emphasis variant made popular by the Maryland Terrapins football team of the 1950s.
• The Tight I is similar to the Maryland I except that the extra back (who happens to be the tight end) is aligned between the quarterback and fullback in the alignment. The split end and the player who normally lines up as flanker are both aligned on the line of scrimmage split away from the end man on the line of scrimmage. This formation was used by the Kansas City Chiefs in Super Bowl IV against the Minnesota Vikings so as to create confusion in the Minnesota defense's lining up against the Chiefs offense.

The I formation, in any variant, can also be modified as Strong or Weak. This formation is commonly called an Offset I. In either case, the fullback lines up roughly a yard laterally to his usual position. Strong refers to a move towards the TE side of the formation (Primary TE, or flanker's side when in a "big" 2TE set), weak in the opposite direction. These modifications have little effect on expected play call. However, the Offset I allows a fullback to more easily avoid blockers and get out of the backfield to become a receiver.