Dollar Sign on the Muscle (1932)

“In his address Monday night, Rickey declared ‘it is hazardous to place the dollar sign on muscle, but professionalism is a natural outgrowth of American progress and possesses most definite elements of permanency.” Associated Press, “Valley League Heads Meet at Keokuk: Rickey Upholds Pros for Stand In Sports Events.” Globe-Gazette (Mason City, IA), January 19, 1932, p11 (Also appeared elswhere)
NOTE: Report on a speech by Branch Rickey of the Cardinals at a meeting of the owners of the Mississippi Valley League.

Previous earliest use (Dickson Baseball Dictionary, 3rd edition, 2009):
No first use given, but the Dictionary notes a similar quote from Rickey in a 1965 book.