As a result of the agreement, the owners of the American Football League created the position of president of the AFL with the mandate to manage the day-to-day affairs of the league semi-autonomously, much like the constituent leagues of Major League Baseball at the time. The owners had hoped that Davis would continue to serve in this role, but Davis (already angry at the owners of the two leagues negotiating a merger without consulting him) refused to serve Pete Rozelle as a subordinate. After Davis resigned as AFL commissioner on July 25, 1966, Milt Woodard (who was assistant commissioner under original commissioner Joe Foss and Davis was appointed AFL president.  The merger paved the way for a new era of prosperity for the NFL. Since 1970, the United States has essentially had only one major professional football league. Other leagues like the XFL, WFL, USFL and UFL have never been a serious challenge for the NFL to fold after one, two, three and four seasons. A league rule, adopted in the wake of the merger, required all NFL teams to use stadiums with more than 50,000 spectators. At that time, several teams had stadiums that did not meet this standard (see above). Most of them built a new stadium until 1971 or, in the case of Chicago, moved to an existing stadium in the subway area that met this requirement. The Buffalo Bills` situation would prove to be a model for future teams; Buffalo`s interests were very slow to agree on a new stadium, and it was only after Bills owner Ralph Wilson began arranging a move to Seattle (a tactic that would then be used by many other teams in their efforts for new stadiums in their hometowns, later with cities like Los Angeles and San Antonio) , Western New York finally agreed to build rich stadium. , which was inaugurated in 1973.
Finally, AFC teams captured the NFC in the mid-1970s. But even then, NFL fans claimed that the three NFL teams that joined the AFC to form the AFC were largely the cause. However, while the Colts and Browns were respectable in the playoffs at that time, it was the Steelers who dominated the league, winning four Super Bowls in a six-year period in the 1970s. From the point of view of AFL fans, it wasn`t a continuation of the “old NFL” – before the merger, the Steelers had long been one of the worst teams in the NFL, recording only eight winning seasons and only one playoff appearance (where they were shut out) since their first year in 1933. They also finished with a 1-13 record in 1969, tied with the Chicago Bears for the worst record in the NFL. The $3 million in moving expenses the Steelers received to join the AFC after the merger (with the win of a Coin-Flip-Tiebreakers against the Bears for the number one in the 1970 NFL Draft, which eventually became the future Hall of Fame Quarterback Terry Bradshaw) helped them rebuild to compete with the other “former NFL teams.”  While the Colts and Browns were respectable playoff contenders during that period, it was the Steelers who dominated the league and won four Super Bowls in six years in 1974-79. From the point of view of AFL fans, this was not a continuation of the former NFL dominance. Before the merger, since their inception in 1933, the Steelers were increasingly close or last in the NFL, including a 1-13 record in 1969 (tied with the Chicago Bears for the worst record in the NFL), with only eight winning seasons and only one playoff appearance (1947, where they were locked out) at that time. The Afl-NFL merger of 1970 was the merger of the two American professional football leagues in the United States at that time: the National Football League (NFL) and the American Football League (AFL).