1. Lead-Off Play: It can refer to the first play in the top half of the first inning when the lead-off hitter of the team batting first comes up to bat and sets the stage for the inning.
2. At-Bat: The first play may also be the initial pitch to a batter during their first at-bat in a game. This is where a batter faces their first pitch in the game.
3. Game-Opening Defensive Play: In some cases, "first play" can refer to the first defensive play made by the team in the field as the game begins. It could be a bunt, a hit ball put into play, or a routine ground out.
4. Pitch: For a pitcher, the "first play" may be their initial pitch of the game or of a specific inning.
5. Double Plays and Outs: In some contexts, "first play" can refer to a double play, triple play, or simply the first out of the game, which is the most important out of any game in terms of preventing a team from scoring.
It's worth noting that the concept of "first play" can vary depending on the specific rules and regulations of different baseball leagues, tournaments, or variations of the sport.