In baseball statistics, games played (denoted by G) indicates the total number of games in which a player has participated (in any capacity). It does not matter in how much of the game the player was active. If player A plays the whole game until there are two out in the bottom of the ninth inning, and then is replaced by player B as a pinch-runner for the final third of an inning, then both A and B are credited with one game played.
See also: Baseball statistics