Plate Discipline (1959)

“Reds’ officials figure if better discipline at the plate will bring more hits, they’re all for it.” Lexington  (KY) Leader (AP), March 5, 1959, p15

‘Naturally they were a little nervous but they showed us good plate discipline.’” Phillies manager Paul Owens after starting three rookies (Craig Robinson, Mike Schmidt, and Bob Boone), all of whom got their first hits. Lebanon (PA) Daily News (UPI), September 13, 1972, p33 (Earliest use of full term)

No earliest use given in 2009 Dickson Baseball Dictionary