How many innings arec played in major league baseball?

There are three answers to this.

First, the Official Game, or Regulation Game. If a game must be called, it is Official after five innings.

Next, the Complete Game. This is nine innings.

And finally, the Extra Innings Game. The only way a Major League Baseball game can end in a tie is if it's called. The rules state that the game must continue until either someone wins or the umpires call the game, usually on account of darkness. In the 2014 season there were two 19-inning games and a handful of 18-inning games; the longest game was 26 innings. The most important rule in extra innings: if a team can't field nine players, it forfeits.