William Young Knowlton (August 18, 1898 – February 25, 1944) was a right-handed baseball pitcher.

[2] According to another, he gained fame as a sandlot pitcher in Philadelphia and then played for Petersburg in the Virginia League.

On September 3, 1920, he started a game for the Philadelphia Athletics against the Washington Senators at Shibe Park.

[4][2] His career record in Major League Baseball was zero wins, one loss, five strikeouts, and a 4.76 earned run average.

[1] Knowlton continued playing in the minor leagues for several years, including stints with the Jersey City Skeeters (1922), Crisfield Crabbers (1922), Wilkes-Barre Barons (1925–1926), Toronto Maple Leafs (1926), and Williamsport Grays (1926–1929).