Reconnaissance player

A reconnaissance player was a term used in Nippon Pro Baseball in the 20th Century. Back when managers did not announce the next day's starting pitcher, NPB teams would use a reconnaissance player in the lineup, who then was lifted for a pinch-hitter based on whether the starters was announced as a lefty or righty. For instance, Sumio Watarai played 65 games in 1968 but never got to bat as he was announced in the starting lineup only to be taken out once the manager knew who the pitcher was. The larger roster sizes in NPB allowed this strategy to be employed.

Source

• Wiki Japan