History of the National Football League on television
NBC was the first major television network to cover an NFL game, when on October 22, 1939, it broadcast a game between the Philadelphia Eagles and the Brooklyn Dodgers; the network was still only in its infancy, with only two affiliates, the modern day WRGB (now a CBS affiliate) in Schenectady and W2XBS in New York City. Portions of that game still survive via films, but the film is not footage from the telecast (recordings of television broadcasts did not begin until 1948). The use of a sideline camera, the sole camera used in the 1939 broadcast, would become the standard for all future NFL broadcasts until 2017; the angle is particularly suited for estimating yardage, compared to more mobile camera angles that began to appear in the 21st century.
NFL on CBS
Two years later, Rozelle would build on this success as the NFL began a four-year experiment of playing on Monday night, scheduling a total of five Monday night games on CBS from 1966 to 1969 (including 2 in 1968). The first prime-time telecast on CBS was on Saturday night, September 10, 1966, with the Baltimore Colts opening the season against the Green Bay Packers at Milwaukee. NBC followed suit in 1968 and 1969 with games involving AFL teams.