Merritt Patrick "Sugar" Cain (April 5, 1907 – April 3, 1975) was an American professional baseball pitcher who worked in 178 games in the major leagues as a member of the Philadelphia Athletics (1932–1935), St. Louis Browns (1935–1936) and Chicago White Sox (1936–1938).

The native of Macon, Georgia, batted left-handed and threw right-handed, stood 5 feet 11 inches (1.80 m) tall and weighed 190 pounds (86 kg).

Over three-quarters of Cain's MLB appearances came as a starting pitcher, and during his career, he amassed 58 complete games and two shutouts.

However, Cain exhibited poor control of his repertoire, allowing more than 100 bases on balls for three straight seasons (1933–1935), leading the American League in walks issued (123) in 1935, and averaging 5.2 walks per nine innings pitched over his big-league career.

Altogether, in 9871⁄3 innings, Cain allowed 1,119 hits and 569 bases on balls, with 279 strikeouts.