The 1884 Brooklyn Atlantics season was a season in American baseball. It was the first season in the American Association for the team, and they finished the year in ninth place. The Brooklyn baseball team had played as the Brooklyn Grays in the Interstate Association in 1883, where they won the championship. In 1884, Charles Byrne moved the team into the American Association, renaming them the Atlantics in tribute to the old National Association Brooklyn Atlantics team.