The Rocklands were unofficially nicknamed the "Rockies" and played as members of the Class D level North Atlantic League from 1946 to 1948.
The Nyack Rocklands became charter members of the Class D level North Atlantic League.
The 1946 North Atlantic League standings featured the first place Peekskill Highlanders (82–32), followed by the Nazareth Cement Dusters (78–40), Stroudsburg Poconos (72–47), Carbondale Pioneers (69–48), Nyack Rockies (67–53), Bloomingdale Troopers (41–78), Mahanoy City Bluebirds (30–79) and Newburgh Hummingbirds/Walden Hummingbirds (27–89).
[1][2][3][4][5] The 1946 Nyack Rocklands finished their first season of play in the North Atlantic League in fifth place with a record of 67–53.
The 1947 season saw Nyack finish with a record of 49–83 and in eighth place in the league standings, playing under manager Emil Schwob.