The Mahanoy City Bluebirds became charter members of the Class D level North Atlantic League as an affiliate of the Boston Braves.
[8] The Bluebirds finished 7th in the North Atlantic League regular season standings with a record of 30–79, playing under managers Buck Boyle and Charles Dugan.
The North Atlantic League standings featured the Peekskill Highlanders 82–32, Nazareth Cement Dusters 78–40, Stroudsburg Poconos 72–47, Carbondale Pioneers 69–48, Nyack Rocklands 67–53, Bloomingdale Troopers 41–78, Mahanoy City Bluebirds 30–79 and Newburgh Hummingbirds/Walden Hummingbirds 27–89.
[9] Beginning play at East End Memorial Stadium, Mahanoy City had home season attendance of 19,261, an average of 353 per game.
Finishing in 4th place under manager Buck Etchison, Mahanoy City was defeated in the Playoffs by the Carbondale Pioneers 4 games to 3.
[15] After a record of 79–54 under returning Manager Buck Etchison, the Brewers were defeated again by the Carbondale Pioneers in the Playoffs, 4 games to 3.
[21][18][17] From 1946 to 1950, Mahanoy City teams were noted to have hosted minor league home games at East End Memorial Stadium.