playbook clearly denotes how the University of Texas ran their version of the single-wing circa 1939–1940. University of Texas Coach Dana X. Bible ran a balanced line, which means that there were the same numbers of linemen on each side of the center. Also, the ends were slightly split. Slightly splitting offensive ends, called flexing, was in widespread use by Notre Dame's Box variation of the single-wing. Knute Rockne's Notre Dame Box offense employed a balanced line, which had 3 linemen on each side of the center. Another Rockne innovation was a shifting backfield that attempted to confuse the defense by moving backs to alternate positions right before the snap. Another variation of the single-wing saw the quarterback move out as a wingback on the weak side. Besides adding different blocking angles for the quarterback, the double-wing formation facilitated the passing game. Stanford had a variation on the double-wing in which the quarterback stayed right behind the strong side guard, while the tailback became the wingback to the weak side. The fullback, being the only deep back left, took all the snaps and directed the plays. The advent of the T formation in the 1940s led to a decline in the use of single-wing formations. For example, the single-wing coach Dana X. Bible, upon his retirement in 1946, saw his replacement, Blair Cherry, quickly install the T formation like many other college coaches of the day. Wallace Wade said he was "not convinced that the single wing is not a more potent formation than the T. The single wing we used caused the defense to spread. It called for more intensive coaching on individual assignments." However, from 1949 to 1957 Henry "Red" Sanders elevated a seldom distinguished UCLA football program to an elite level with his precision single-wing system, winning a National Championship at UCLA in 1954. The single-wing style of football is still practiced by a small group of teams across the country, almost exclusively at the high school and youth level. The Pittsburgh Steelers were the last NFL team to use the single-wing as their standard formation, finally switching to the T formation in 1952. In 2008, the Miami Dolphins utilized a version of the single-wing offense (calling it the "wildcat") against the New England Patriots on six plays, which produced four touchdowns in a 38–13 upset victory, and again two weeks later defeating the San Diego Chargers.