James Blaine "Rifle Jim" Middleton (May 28, 1889 – January 12, 1974) was a professional baseball player.

He was a right-handed pitcher over parts of two seasons (1917, 1921) with the New York Giants and Detroit Tigers.

For his career, he compiled a 7–12 record in 51 appearances, with a 4.51 earned run average and 40 strikeouts.

He was born and later died in Argos, Indiana, at the age of 84.

This biographical article relating to an American baseball pitcher born in the 1880s is a stub.