An old Earth bat-and-ball sport that had died out as a professional game by the mid twenty-first century, kept alive in the twenty-fourth by enthusiasts such as Benjamin Sisko and his son Jake.
Baseball had lost its audience on Earth by 2042, the year of the last World Series, but Benjamin Sisko loves it and shares it with his son through holosuite recreations of great players. In Emissary he uses the game to explain linear time to the Prophets: nobody knows how a pitch will turn out, and that is the point of playing.
In If Wishes Were Horses an image of Buck Bokai, the London Kings shortstop who broke Joe DiMaggio's hitting streak, steps out of the holosuite. Family Business reveals that the colonists of Cestus III have revived the sport with a league of their own, in which Kasidy Yates's brother plays.
The game takes centre stage in Take Me Out to the Holosuite, when Sisko's scratch team, the Niners, is soundly beaten by a Vulcan side called the Logicians and celebrates anyway.