Alonzo Sheck "Shack" Shealy (June 1, 1873 – October 24, 1929) was a college football player and coach.
He was the fifth head coach of the Clemson college football program in 1904, and the only Clemson graduate (1899) to be head coach of his alma mater.
A member of Clemson's first football team in 1896, Shealy served as team captain in 1898.