John Kirkland Clark, Sr. (January 21, 1877 – January 20, 1963) was an American lawyer, college basketball player and the first head coach of the Harvard College men's basketball team.

[2] Clark served as a member of the Loyalty Review Board established by U.S. President Harry S. Truman.

[3][4] Clark grew up in Springfield, Milwaukee, Washington DC and Philadelphia before his family settled in Brooklyn.

[5] Clark graduated from Yale College in 1899 and from Harvard Law School in 1902.

[7] Clark played three seasons for Yale College men's basketball from 1896 to 1899 as a 5'10" 160 lb Guard.