A substitute player is an athlete who is not part of the starting lineup in a sports game but is available to replace a player during the match. This allows teams to adjust their strategy, manage player fatigue, or respond to injuries. Substitute players can enter the game at specific times, depending on the rules of the sport. In many sports, such as soccer and basketball, teams have a limited number of substitutes they can use. The role of a substitute player is crucial, as they can bring fresh energy and skills to the game, potentially influencing the outcome.