John A. Armstrong, Jr. (August 10, 1897 – April 30, 1960) was an American football player and coach. After attending the University of Dubuque, where he was a four-sport athlete, he coached at Columbia College, in addition to managing a recreation hall. Armstrong played on the Rock Island Independents of the National Football League, and later the first American Football League, from 1923–1926. The Green Bay Press-Gazette named Armstrong a third-team All-Pro in 1923. That season, Armstrong was the NFL leader in passing yards and passes intercepted, according to unofficial statistics.
In 1924, Armstrong coached the Independents to a 5–2–2 record, and a fifth-place finish. For his last professional football season, 1926, he also served as coach for Rock Island in the AFL; the Independents were 2–6–1 that year. Armstrong also played minor league baseball for the Dubuque Climbers/Dubs/Ironmen and Oklahoma City Indians from 1922 to 1928.