Extra innings

Extra innings is the extension of a baseball or softball game in order to break a tie.

Ordinarily, a baseball game consists of nine regulation innings (in softball and high school baseball games there are typically seven innings; in Little League Baseball, six), each of which is divided into halves: the visiting team bats first, after which the home team takes its turn at bat. However, if the score remains tied at the end of the regulation number of complete innings, the rules provide that "play shall continue until

(Since the home team bats second, condition (2) does not allow the visiting team to score more runs before the end of the inning, unless the game is called before the inning ends).

Most of the rules of the game, including the batting order, availability of substitute players and pitchers, etc., remain intact in extra innings, although occasionally leagues and tournaments will place runners on base to start extra innings in order to speed up the game. Managers must display caution to avoid exhausting all their substitute players during regular innings, in case the game reaches extensive extra innings. The rules call for a forfeiture if a team is unable to field a full team of nine players.

In Major League Baseball, home teams won about 52% of extra-inning games from 1957 to 2007. During this same time period, home teams have won about 54% of all baseball games. So while the home team has some advantage in extra-inning games, this advantage is less noticeable than the initial home-field advantage. Home teams tend to have the greatest advantage in run-scoring during the first 3 innings.

For the visiting team to win, it must score as many runs as possible in the first (or "top") half of the inning and then prevent the home team from tying or taking the lead in the second (or "bottom") half. Because it bats in the bottom half of an inning, a home team wins the game by taking the lead at any point in the final inning. Normally in such a situation, the moment the winning run scores for whatever reason (base hit, sacrifice, wild pitch), the game immediately ends and no other runs are allowed. The term for winning in this scenario is a "walk-off" win (as everyone can walk off the field as soon as the winning run is scored). The exception is if the winning hit is a walk-off home run; all runners on base and the batter must circle the bases on a home run, provided that they round them all correctly, so all their runs count for the final score. Each extra inning simply repeats this scenario. This is in contrast to the analogous penalty shootout used in ice hockey or association football, where shootout goals are counted separately and only one goal is awarded to the winner (hockey), or the game is recorded as a draw and the team winning the shootout is noted separately (association football); however, the same procedure of counting runs as if they were scored in regulation is like the overtime procedures in American football, Canadian football and basketball.

The East Asian professional leagues, NPB, and CPBL have a 12-inning limit before the game is declared a draw. Starting in 2025, the KBO will have an 11-inning limit on single games and the second game in a doubleheader, and a nine-inning limit in the first game of the doubleheader (no extra innings).

Additionally, NPB games have a total time limit of 210 minutes during the regular season before being counted as a tie. Postseason play has reduced the number of innings allowed. Until 1986, the Japan Series had a 270 minute (4 hours, 30 minutes) time limit. From 1987 to 1993, it was changed to 18 innings; from 1994 to 2017, it was 15 innings. In the Climax Series, and in the Japan Series since 2018, postseason play rules are the same as the regular season in 12 innings (except in 2020 and 2021, when no extra innings were played in the regular season and first two rounds of postseason, 12 inning limits were used in the Japan Series). In case of a drawn game, it is completely replayed as usual. A seven-game series can be extended to an eighth game or subsequent game, something that has happened only once (in the 1986 Japan Series). Starting in the eighth and subsequent game in the Japan Series, the 12-inning limit does not apply, and the game is continued until a winner is decided. Since 2021, a modified 12-inning limit is used in such games; beginning in the 13th inning, the two-runner WBSC tiebreaker will be implemented, similar to the current high school tournament rule. The two batters in the batting order before the player at bat will take first and second base.