home run ball (1886)

“O’Brien made an elegant running catch of an almost home run ball from Werden’s bat.” “A Better Game,” Rocky Mountain News (Denver), September 5, 1886, p3

“Roseman says Burns’s home-run ball went over the fence fair, and Roseman ought to know.” “Base-Ball Notes,” Baltimore Sun, August 11, 1887, p3

Previous earliest use (Dickson Baseball Dictionary, 3rd edition, 2009):
1937.  (Philadelphia Record; Sept. 28; Edward J. Nichols).