“Wes Ferrell was to have faced the Athletics in the fourth game of the series tomorrow, but his long relief assignment Sunday eliminated him….” Cleveland Plain Dealer, July 12, 1932, p13
“Dizzy Defeated by Philadelphia. Passeau Again Pitches Well in Long Relief Role for Phils.” (Headline). Clarion-Ledger (Jackson, MS), July 17, 1936, p14
- NOTE: The Ferrell description seems simply a use of the adjective “long” to describe a particular relief appearance. The Passeau description for a role that he had filled before seems a closer fit to the phrase.
No earliest use given in Dickson Baseball Dictionary