The steering committee for the 90th Spring Koshien (Senbatsu) met in Osaka on January 10 and selected Ima Arite for the opening march. Ima Arite is also currently the tournament song. The thirty-six participating high schools will be decided by the selection committee on January 26.
The following tie break rules will also be introduced, not just to the Spring Koshien, but also to the Summer Koshien and various spring, summer, and fall tournaments.
- the tie break will be used beginning in the thirteenth inning. Innings will begin with runners on first and second and no out.
- the batting order will resume where it ended in the previous inning.
- if the game has to be canceled after the start of a tie break, the game will end in a tie and a rematch will be played on the following day (or at the earliest possible date).
- if the game is still tied after the fifteenth inning, the game will continue, however, each pitcher will be limited to a total fifteen innings. Pitchers that reach fifteen innings will only be able to continue playing as a position player.
- the tie break will not be used during the final game. If the game is still tied after fifteen innings, then the game will end and a rematch will be played the following day (or at the earliest possible date). The tie break will be used for the rematch game.
- the two runners on base at the start of tie break innings will not count as earned runs if they score. The two runners will not get credit for being on base. Stolen bases, caught stealing, runs, and left on base will count, as will other stats connected to the runners, like RBI and double plays.
- there will be no complete games.
- there will be no hitters.
Source: Nikkan Sports 1/10/2018, Nikkan Sports 1/10/2018, Daily Sports 1/10/2018, Daily Sports 1/10/2018