When he took over in 1960, as a little known fallback choice of the league's owners after 23 rounds of voting, professional football was chickenfeed - an uninspiring hotchpotch cluster of local teams, local markets and purely local enthusiasms. By the time he retired, the NFL had outstripped major league baseball to become a national institution, the country's richest, best run and most widely followed sport.
In a business dominated by short-term greed rather than long-term vision, Pete Rozelle was the exception. From the outset he understood three things: the vast possibilities of television for the sport, the need for financial equality between clubs and that, to ensure the credibility of the product, no star could be bigger than the game.
Rozelle began his NFL career in 1952, when he joined the Los Angeles Rams as their public relations director. Five years later he became their general manager, and it was from this position that he took over the NFL.
The NFL Rozelle inherited at the age of 33 consisted of just 12 teams, with hugely varying resources. Back in 1960, the New York Giants could sell their television rights for $350,000 a year, but the Green Bay Packers from remote northern Wisconsin could command only a tenth of that. Displaying the gift for compromise that would be a hallmark of his tenure, Rozelle persuaded the owners not only to allow him to negotiate a single television deal for the entire league - but to share the proceeds equally.
Thus was born the concept of revenue sharing that today generates $40 million of television income for each of the NFL's 30 teams. Two years ago, baseball was paralysed by the longest ever strike in sports history over the very same issue, which to a lesser extent torments icehockey and basketball.
The NFL has had its share of turmoil over the years, including three strikes by unionised players and countless spats over franchises: in what other sport would the shift of a team from Cleveland to Baltimore require round-the-clock police protection and be a subject of debate in Congress? But revenue sharing is an accepted article of faith. And the $1.6 billion four-year deal in 1993 with Fox television is the measure of the NFL's unrivalled popularity.
Finally, Rozelle insisted on a clean house. Back in 1963 he banned two of the sport's top stars, Alex Karras and Paul Hornung, for gambling, and despite several well-advertised drug scandals, football is still strictly run today. That incidentally was the year of what the commissioner acknowledged as his "great mistake," permitting play on 24 November, two days after the assassination of President Kennedy.
But that controversy has long since settled. Pete Rozelle's lasting legacy is the changed habits of his fellow countrymen. In 1970 he merged the NFL with the rival American Football League - but not before instigating a regular season finale game between their respective champions. Later it would be called the Super Bowl, the single biggest event on America's sporting calendar, bigger than hockey's Stanley Cup or the NBA basketball championship, bigger even than the World Series.
But even the ordinary NFL season has transformed American weekends. For three hours each Sunday afternoon in winter the streets of major cities are eerily deserted because of televised football. To the mix Rozelle then added that other institution of Monday Night football, bringing the sport into tens of millions of homes in midweek prime time, and forcing cinemas and bowling alleys to shut down in droves while the game was on.
Even Thanksgiving has been reshaped by the NFL. A televised afternoon game is as much a part of America's great family holiday as turkey, pumpkin pie and a visit from the grandparents. Few Presidents can claim as much.
Alvin Ray (Pete) Rozelle, sports executive: born 1 March 1926; General Manager, Los Angeles Rams football club 1957-60; Commissioner, National Football League 1960-89; died Rancho Santa Fe, California 6 December 1996.