Brannan began his professional career in 1926, split between the Class-C Muskogee Athletics and the Class-A Tulsa Oilers.

[1] Brannan became the first attendee of Arkansas State University to play in the major leagues when he made his debut.

Over his two years with the Browns, Brannan played 154 games at second base and committed 28 errors in 812 total chances.

Brannan began his tenure with the Double-A Hollywood Stars of the Pacific Coast League in 1930 after he signed in February of that year.

At the end of the season, the Stars reportedly contemplated a trade involving Brannan to the Cleveland Indians, but nothing was ever finalized.

[8] Brannan returned from retirement in 1936 to join the Class-D Osceola Indians of the Northeast Arkansas League.

After a one-year absence from professional baseball, Brannan returned in 1938 with the Class-C Hot Springs Bathers of the Cotton States League.

In 1940, Brannan began his managerial career as a player-manager with the Class-D Lake Charles Skippers of the Evangeline League.

Brannan only played one game with the Class-D Lafayette White Sox, who were affiliated with the St. Louis Browns.