First, second or third

BASE

["Think of what runners touch in a diamond-shaped path or what a batter aims to reach safely in a ballgame."]

"First, second or third" hints at positions in a sequence, which in baseball are called bases—first base, second base, and third base. The word "base" fits neatly as the answer since it’s the term for those specific spots on the field. The clue plays on the double meaning of "base" as both a position in order and a key part of the sport.