If a player serves as a courtesy runner and later wishes to pinch-hit in the same half-inning, what is the ruling?

The correct ruling regarding a player serving as a courtesy runner and subsequently wishing to pinch-hit in the same half-inning is that the player is restricted to the bench. Once a player has participated in a game as a courtesy runner, they are considered to have been a part of the game in that capacity for that half-inning. Consequently, they cannot then legally enter the game to perform another role, such as pinch-hitting, within the same half-inning.

This ruling is rooted in the intent of maintaining fair play and ensuring that substitutions and roles are clearly defined throughout the game. Each player has specific roles they can fulfill in any given half-inning, and switching roles in this manner is not permitted. Thus, a player who has served as a courtesy runner cannot transition back into the game for a different role until the next half-inning.