After a red is potted, the cue ball finishes in a cluster of reds. Another red struck by the white but still moving comes to rest in the cluster leaving the player not only snookered but with the the cue ball completely surrounded by reds with no gaps.
Discussed on this forum but with no examples of it actually happeninghttps://www.thesnookerforum.co.uk/board/forum/snooker-forums/snooker-questions/12180-what-happens-if-cue-ball-is-surrounded
The 2nd one in this vid is fairly close to it, I don’t think he can hit a cushion. I think Fu helps him out a bit.
https://m.youtube.com/watch?v=P1JB3inHIM0The 2nd one in this vid is fairly close to it, I don’t think he can hit a cushion. I think Fu helps him out a bit.