“Mr. Fenno, the official scorer of the Boston nine, has furnished the following record of the individual players, which shows the successes and failures of each in the various positions:” The Boston Daily Globe, November 16, 1874, p2
Previous earliest use (Dickson Baseball Dictionary, 3rd edition, 2009):
1ST USE. 1875. “The base ball reporter of the Republican and the official scorer of the St. Louis Base Ball Club are one and the same person” (St. Louis Globe-Democrat, June 26).