Diamonds is a baseball game from the perspective of the team manager. Each manager has a set of player cards, each with individual skills ratings. Players determine the batting order and starting pitcher. As the game plays out, players can make substitutions and other managerial decisions. The game is sold both as a Basic Edition, with 4 different teams, and a League Edition with 6 teams and un-laminated player cards (so that managers can name their own players). Both use the same rules. The game contains four or six 25-card team decks, several other play cards, a sheet of uncut markers, and four dice.