Free Substitution Rule 1950 No longer did the same players play on offense and defense In 1950 the NFL adopted the free-substitution rule that introduced the modern pro football game. Football History Because fans were packing the NFL stadiums the league teams could afford squads of 35 men. Coaches could train offensive and defensive teams. Specialists appeared. The big man who was hard to move and was fast enough to rush the passer was wanted on the defensive team’s forward wall. The fast back who could also tackle and run back intercepted passes for yardage went into the defensive secondary. On the offensive teams were the best passers, runners, blockers and pass receivers. And of course there was the man who came into the game only to kick placements or to punt.
The age of the specialist, with the accent on the forward pass, had actually begun in 1945. In that year quarterback Bob Waterfield led the Rams (then in Cleveland) to the league title. Thereafter, no team would win a title without a great quarterback at the helm. In 1946 it was Sid Luckman and the Chicago Bears; in 1947 Passin’ Paul Christman and the Chicago Cardinals; in 1948 and 1949 one-eyed Tommy Thompson of Tulsa put the Philadelphia Eagles on top. The following year it was quarterback Otto Graham and the Browns; in 1951 it was Waterfield and Norm Van Brocklin with the Los Angeles Rams. Bobby Layne and the Detroit Lions did it in 1952 and 1953; Otto Graham was on top again in 1954 and 1955. In 1956 the elderly gentleman from Mississippi, Chuckin’ Charley Conerly, led the Giants home; and Bobby Layne was the star again in 1957. Quarterback Johnny Unitas brought the Baltimore Colts out of nowhere to the top in 1958 and 1959. In 1960 it was Van Brocklin again, this time with Philadelphia. For the next two years Bart Starr shone for the Green Bay titlists; and in 1963 Billy Wade put the Chicago Bears out in front.
The following from a book ‘The Story of Football’ by Robert Leckie - 1965 Edition In 1946 Elmer Layden resigned as NFL Commissioner and Bert Bell took his place. Bert Bell was the old Penn star and had brought pro football to Philadelphia. Under him, the NFL weathered its battle with the All-America Conference, and pro football began to explode. By the time of Bert Bell’s death in 1959, the twelve-team NFL was playing to more than three million paying customers every year. Under young and energetic Alvin ‘Pete’ Rozelle, who eventually succeeded Bert Bell, the annual ‘gate’ rose to more than four million fans in 1962. It keeps rising every year. In some cities in the National League it is next to impossible to buy a ticket to a home game. The only way to secure a season’s ticket is to inherit one. In 1963, the franchise of the Los Angeles Rams sold for $7,100,000. In 1941 that same franchise had been worth only $100,000. Twenty years before that, a pro franchise went for just one hundred dollars. Some experts say that the 1963 franchise, worth more than seven million dollars, may be a better risk than the one that went for a mere hundred. That is because the possibility of pay television may open up even more profitable frontiers. And it is also because television has enabled pro football to challenge pro baseball as the national pastime.