I formation The I formation is one of the most common offensive formations in American football . The I formation draws its name from the vertical ( as viewed from the opposing endzone ) alignment of quarterback , fullback , and running back , particularly when contrasted with the same players ' alignments in the " T formation " . The formation begins with the usual 5 offensive linemen ( 2 offensive tackles , 2 guards , and a center ) , the quarterback under center , and two backs in - line behind the quarterback . The base variant adds a tight end to one side of the line and two wide receiver s , one at each end of the line . History . The exact origin of the I formation is unclear . Tom Nugent is credited with developing the I formation at Virginia Military Institute in 1950 as a replacement for the single - wing and an alternative to the T formation . Don Coryell , before popularizing Air Coryell , was also a pioneer of the I and used it as a high school coach in Hawaii , at Wenatchee Valley College in 1955 , and at Whittier College in 1957 - 1959 . In 1960 , Coryell was an assistant coach under John McKay for the USC Trojans . By 1962 , McKay ' s USC team won the national title with an offense built on the I . John Madden recalled going to an I formation clinic led by McKay . " We ' d go to these clinics , and afterward , everyone would run up to talk to McKay , " said Madden . " Coryell was there because he introduced ( McKay ) . I was thinking , ' If ( McKay ) learned from him , I ' ll go talk to ( Coryell ) . ' " Tom Osborne , head football coach at Nebraska , further popularized the formation in the early 1970s ( while the offensive coordinator under head coach Bob Devaney ) . It was the base of the Nebraska option offense for over thirty years . NFL teams followed the success of the I at the college level and adopted it as well . Typical roles . The I formation is typically employed in running situations . In the I formation , the tailback starts six to eight yards behind the scrimmage from an upright position , where he can survey the defense . The formation gives the tailback more opportunities for finding weak points in the defense to run into . The fullback typically fills a blocking , rather than rushing or receiving , role in the modern game . With the fullback in the backfield as a blocker , runs can be made to either side of the line with his additional blocking support . This is contrasted with the use of tight ends as blockers who , being set up at the end of the line , are able to support runs to one side of the line only . The fullback can also be used as a feint — since the defense can spot him more easily than the running back , they may be drawn in his direction while the running back takes the ball the opposite way . Despite the emphasis on the running game , the I formation remains an effective base for a passing attack . The formation supports up to three wide receivers and many running backs serve as an additional receiving threat . While the fullback is rarely a pass receiver , he serves as a capable additional pass blocker protecting the quarterback before the pass . The running threat posed by the formation also lends itself to the play - action pass . The flexible nature of the formation also helps prevent defenses from focusing their attention on either the run or pass . Common variations . Many subtypes of the I formation exist , generally emphasizing the running or passing strengths of the base version . 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 . In professional football . In the NFL , the I formation is less frequently used than in college , as the use of the fullback as a blocker has given way to formations with additional tight end s and wide receiver s , who may be called on to block during running plays . The increasingly common ace formation replaces the fullback with an additional receiver , who lines up along the line of scrimmage . The I will typically be used in short - yardage and goal line situations .