How does the typical knuckle ball work?

The bowler runs in with the ball like he normally does. There is no change in the run up, load up or arm speed. What is different is the grip. While seamers typically hold the ball with their fingers over the seam in an upright position (or with the seam slightly tilted / pointing towards the slips or fine leg), in this case, the ball is gripped between the thumb and the tip of the fingernails, with the ring finger providing support. Some bowlers prefer folding their index and middle fingers so that the fingernails are completely behind the ball. The thumb and seam position remain the same (like a regular seam-up delivery), but the tips of the fingernails (of the index and middle finger) behind the ball cause it to travel slower through the air and dip sharply. Image sources: https://www.perthnow.com.au/sport/perth-scorchers/perth-scorchers-ace-aj-tye-reveals-how-he-bowls-six-of-his-key-deliveries-ng-b88695334z Essentially a slower delivery, what makes the knuckle ball so special is the fact that for the batsman, it looks like the bowler has released a stock seam-up delivery. There is hardly any difference in the release from a batsman’s point of view (unlike the offcutters and legcutters). Another advantage for the bowler is that the ball has negligible backspin (or rotations) and when pitched on a good length or even fuller, it dips unexpectedly, thus making it harder for the batsman to negotiate. What’s more, if it is swinging, bowlers like Bhuvneshwar Kumar have even bowled this at the beginning of an innings, making it wobble unpredictably.