High school baseball runs on the NFHS rulebook, and its substitution rules trip up more coaches than any other part of the game. Get them right and you keep your options open; get them wrong and you risk an illegal-substitution penalty.
Starters re-enter once; subs do not
Under NFHS Rule 3-1-3, a starter may leave the game and re-enter one time, but must return to the original spot in the batting order. A substitute who enters and is later removed may not re-enter at all. Knowing who is a starter with a re-entry left versus a spent substitute is the whole game.
The designated hitter
Most states allow a DH, who bats for one defensive player. Set the DH once and choose which fielder they hit for. A common mistake: if the player being hit for comes up to bat for themselves, the DH role ends for the game.
The two-way Player/DH
NFHS allows a player to be both a fielder (often the pitcher) and the DH at once — batting for themselves rather than for another player. This “Player/DH” occupies one spot in the order and one on the field. If they later leave the mound but keep hitting, the rules still treat it carefully, which is why a tool that tracks it helps.
Courtesy runners
A courtesy runner is allowed for the pitcher and catcher, once per inning, and does not count as a substitution — so it never costs you a re-entry.
Our High School builder tracks each player’s re-entry status and flags moves the rulebook does not allow. Always confirm against the current NFHS rules and any state associations’ modifications.