National Association of Professional Base Ball Players
National Association of Professional Base Ball Players (NAPBBP) (Nacionalno udruženje profesionalnih igrača bejzbola) ili, skraćeno, National Association (NA) (Nacionalno udruženje) je američka profesionalna bejzbol organizacija koja je djelovala od 1871. do 1875. godine. Nastala je raspadom dotadašnje National Association of Base Ball Players (NABBP) na profesionalne klubove - koji su se udružili u NA - i amaterske klubove koji su kraće vrijeme djelovali kroz organizaciju National Association of Amateur Base Ball Players. NA je važna za historiju bejzbola zbog toga što je predstavljala prvu profesionalnu bejzbol ligu. Godine 1876. mnogi njeni klubovi su stvorili National League, koji dan danas postoji u okviru Major League Baseballa.
- Boston - Boston Red Stockings (1871–1875)
- Chicago - Chicago White Stockings (1871; 1874–1875)
- Forest City - Cleveland Forest Citys (1871–1872)
- Kekionga - Fort Wayne Kekiongas (1871)
- Mutual - New York Mutuals (1871–1875)
- Athletic - Philadelphia Athletics (1871–1875)
- Forest City - Rockford Forest Citys (1871)
- Troy - Troy Haymakers (1871–1872)
- Olympic - Washington Olympics (1871–1872)
- Atlantic - Brooklyn Atlantics (1872–1875)
- Eckford - Brooklyn Eckfords (1872)
- Lord Baltimore - Baltimore Canaries (1872–1874)
- Mansfield - Middletown Mansfields (1872)
- National - Washington Nationals (1872-1873; 1875) Washington Blue Legs (1873)
- Maryland - Baltimore Marylands (1873) (igrali na Madison Avenue Grounds)
- Philadelphia - Philadelphia White Stockings (1873-1875) (ponekad poznat kao "Pearls" ili "Phillies")
- Resolute - Elizabeth Resolutes (1873)
- Hartford - Hartford Dark Blues (1874–1875)
- Centennial - Philadelphia Centennials (1875)
- Elm City - New Haven Elm Citys (1875)
- St. Louis - St. Louis Brown Stockings (1875)
- St. Louis Reds - St. Louis Red Stockings (1875)
- Western - Keokuk Westerns (1875)
- David Pietrusza Major Leagues: The Formation, Sometimes Absorption and Mostly Inevitable Demise of 18 Professional Baseball Organizations, 1871 to Present Jefferson (NC): McFarland & Company, 1991. ISBN 0-89950-590-2
