“The average number of times in which they made first base by clean hits in a match was 40 and over, showing a good batting average.” The Brooklyn Union, December 4, 1869, p1
“The following are the batting averages of the Athletic ten for 1870.” The New York Times, November 20, 1870, p5
“Prior to the departure for England, the batting average of the Boston club was made out, by which George Wright takes the lead, having made 54 base hits in 139 times at bat in 27 games, or a percentage of .388; Spalding was second with 75 first base hits in 198 times at bat in 38 games, a percentage of .378.” The Boston Daily Globe, August 10, 1874, p5
- NOTE: The first two refer to average hits per game. It’s not clear if the March 29, 1874 reference shown as in the 2009 Dictionary (see below) uses that sense or the modern one. Hits per game appears to have been the more common usage at least through 1876. The term was also used much earlier in cricket.
The following article seems to use batting average in the current sense, but it is confusing. It shows “times to the bat” and [times reaching] “first bases” and an average, shown as two digits without the decimal. But it is not clear what the last column of numbers represents.
“The batting average of the Bostons is shown by the following table:” Boston Daily Globe, August 19, 1872, p5
Previous earliest use (Dickson Baseball Dictionary, 3rd edition, 2009):
1874. “The following players led the batting averages of first base hits” (Brooklyn Eagle, March 29; Peter Morris).