A Fielder’s Choice occurs when a defensive player fields a batted ball on which with normal effort he could have put the batter out at first base, but instead chooses to make a play on another runner.
Most commonly, a Fielder's Choice results in a force out on another runner. For example, on a ground ball to shortstop, the fielder throws to second base for an out.
When a fielder attempts to make a play on a runner, rather than the batter, it is scored a Fielder's Choice even if the play does not result in an out. Example – with a runner on third, the pitcher fields a ground ball and unsuccessfully attempts to throw out a runner from third base.
When a fielder fields a ball cleanly, but makes a mental error and throws to the wrong base, fails to step on a base for a force, or fails to make the correct play, the scorekeeper should score the play as a Fielder's Choice, rather than as an error.
When the batter makes a base hit on which fielders attempt to make a play on other runners (whether successful or not) and the batter advances further than he would have with the bases empty, the scorekeeper should score the hit accordingly and indicate the additional bases as taken by Fielder's Choice. For instance, batter singles to center field, but takes second when the outfielder throws home, the play should be scored as 1B, noting the runner advanced to second on a Fielder's Choice.