991 System (991 시스템)No-spin short–long–short, to the 4th and 5th cushions

A system used for the short–long–short (단장단) path with a no-spin stroke which, unlike the other systems, targets the 4th and 5th cushions. The cue ball leaves from the short cushion and aims at the opposite short cushion, comes to the long cushion, the short cushion it started from and again the opposite short cushion (4th cushion); if the 4th cushion shifts onto the long cushion, the ball continues to the 5th cushion. It is used in 세워치기 (steep-angle shot) and 비껴치기 (thin, grazing hit on a ball near the cushion) positions, as well as in bricole shots. The calculation is a single subtraction.

When? When the cue ball is near the bottom short cushion (or its line passes through the bottom short cushion) and ball 3 is waiting on the top short cushion or in the upper half of the right long cushion, i.e. in the 4th-cushion zone.