John Ellett Herrnstein (March 31, 1938 – October 3, 2017) was an American baseball and football player. He played Major League Baseball from 1962 to 1966 for the Philadelphia Phillies, Chicago Cubs, and Atlanta Braves. He also played college baseball and football at the University of Michigan from 1956 to 1959. He was the captain of the 1958 Michigan Wolverines football team and the third generation of the Herrnstein family to play for a Michigan Wolverines football team. His father, William Herrnstein, Jr., played for the Wolverines from 1923 to 1925, and his grandfather, William Herrnstein, Sr., played for the team in the 1898 and 1900 seasons. His great uncle Albert E. Herrnstein played for Fielding H. Yost's famed "Point-a-Minute" teams in 1901 and 1902.