Every player starts with a capital of 501 points. The player throws a round of three darts (or less) and the score is added up. The result is subtracted from the player's capital, the aim being to reach exactly zero before the other player (without going past this figure). In order to reach zero, the player must throw the last dart of the leg into a "double" ring or the double centre (the term double out from the name of the game). If the player goes past zero, the whole of the round in hand is nullified.