1920
Brooklyn City return to the top of the table, edging Chicago West End by a point. Washington City finishes 3rd, another point back. This is the closest three-way finish(excluding ties) in Premiership history.
1921
PL mandates that tie-breaking games be played to determine relegation and promotion positions.
Additionally, new rules on tie-breakers for the Premiership are adopted. Head-to-head competition remains first, followed by record vs. teams in order of standing and points for-points against.
Tiebreakers don't come into play this year at the top of the table, however, as Brooklyn City repeats as Premier, 5 points clear of Spring Garden.
1922
The Bounce Pass is adopted for the first time.
PL bylaws are amended to allow for Sunday games, but only in cities that allow Sunday play, and only in case of rainouts. By a single vote, night games were rejected.
In the Premiership, Toronto United becomes the first Canadian team to win the Premiership, winning by 4 points over St. Paul City.
1923
A third division, proposed before World War I, is finally added. 26 teams join, with 4 promoted to the 2nd division. Because of expansion, no team from the 1922 1st division are relegated.
In the 1st division, New York Scotch wins it's third Premiership by 3 points over Toronto United. Washington City finish 19th, it's worst finish ever.
1924
The Columbians add 18-year old Nick Ryan, who starts his first game at the National Stadium, and move up to 8th in the 1st division. Premiership honors go to Boston Rovers, 4 points clear of New York Scotch. Ryan scored 40 goals this season.
1925
Nick Ryan scores 77 goals in 46 games to guide Washington City to it's first Premiership since 1910, and starts off the greatest dynasty the game has ever known. Detroit City(renamed from Detroit Grande starting this season) finish 7 points back.
1926
The restrictions on Sunday games are relaxed again, eliminating the rule that only rained out games can be played that day.
Washington City repeat as Premiers, winning the title by 11 points over New York Scotch.
1927
Pittsburgh Commission standardizes rules for all pigball competitions. This include awarding 2 points for wins, 1 point for ties and no points for losses. Most leagues, outside the PL, had until this point utilized win-loss percentage in determining standings. Also mandated were goal posts affixed to goals, a ban on the bounce pass and a fixed sized for the dimensions of the field; 300 feet in length, 210 feet in width.
Despite the new rules, Washington City wins the premiership for an unprecedented 3rd straight season, by 2 points over Boston Union.
1928
Length of the field is adjusted from 300 to 360 feet, opening up play.
Colonel Roberts retires as Pigball League president, replaced by Kent Stover, who relocates the league's headquarters to New Haven, Connecticut.
NBC Radio broadcasts the first pigball game on national radio, carrying the July 4th game between Georgetown United and Baltimore PC.
With Nick Ryan becoming the first PL player with 100 or more goals in a season(105 to be exact), Washington City win their fourth Premiership in a row, by 7 points over Richmond.
1929
The width of the field is narrowed to 180 feet. After this, the only alterations to the design of the field are restricted to markings.
The Columbians win their 5th Premiership in succession, and by the biggest margin yet, 14 points over Georgetown and Minneapolis.