Daniel Lucius "Doc" Adams (November 1, 1814 – January 3, 1899) was an American baseball player and executive who is regarded by historians as an important figure in the sport's early years. For most of his career he was a member of the New York Knickerbockers. He first played for the New York Base Ball Club in 1840 and started his Knickerbockers career five years later, continuing to play for the club into his forties and to take part in inter-squad practice games and matches against opposing teams. Researchers have called Adams the creator of the shortstop position, which he used to field short throws from outfielders. In addition to his playing career, Adams manufactured baseballs and oversaw bat production; he also occasionally acted as an umpire.