4.10
(a) A regulation game consists of nine innings, unless extended because of a tie score, or shortened (1) because the home team needs none of its half of the ninth inning or only a fraction of it, or (2) because the umpire calls the game. EXCEPTION: National Association leagues may adopt a rule providing that one or both games of a doubleheader shall be seven innings in length. In such games, any of these rules applying to the ninth inning shall apply to the seventh inning.
( If the score is tied after nine completed innings play shall continue until (1) the visiting team has scored more total runs than the home team at the end of a completed inning, or (2) the home team scores the winning run in an uncompleted inning.
© If a game is called, it is a regulation game:
(1) If five innings have been completed;
(2) If the home team has scored more runs in four or four and a fraction half-innings than the visiting team has scored in five completed half-innings;
(3) If the home team scores one or more runs in its half of the fifth inning to tie the score.
(d) If a regulation game is called with the score tied, it shall become a suspended game. See Rule 4.12.
(e) If a game is called before it has become a regulation game, the umpire shall declare it “No Game.”
(f) Rain checks will not be honored for any regulation or suspended game which has progressed to or beyond a point of play described in 4.10©
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