Nine-ball

In nine-ball, the objective is to legally pocket the 9-ball, and you can win the game early by sinking it at any time, provided you strike the lowest-numbered ball on the table first. This is known as a "combination shot" or "money ball" shot. If you sink the 9-ball in a legal manner before clearing all the other balls, you instantly win the rack.

If the cue ball goes into a pocket or off the table on the break shot, it is considered a foul in professional nine-ball. Under World Pool-Billiard Association (WPA) rules, the incoming player is awarded "ball in hand," meaning they can place the cue ball anywhere on the table to take their shot. This severe penalty makes scratching on the break highly detrimental.

Nine-ball is traditionally played with the classic rule where any ball that goes into a pocket on a legal break stays down, allowing for slop (unintentional pocketed balls). Ten-ball was adapted later specifically to require players to call their shots, removing the element of luck. Additionally, ten-ball uses ten balls instead of nine, with the 10-ball acting as the final game-winning ball.

Nine-ball is currently the primary discipline for the WPA World Nine-ball Championship, a major international event historically dominated by players from the Philippines and Taiwan. Matchroom Sport, the organizer of the Mosconi Cup, heavily promotes this fast-paced format. The quick gameplay and aggressive shot-making required by the rules make it the most televised cue sport globally.