Figure 2

On the left side are represented the 8 facets of the butt cap and the reference points (base knuckle of the index finger and heel pad) on the hand to identify the different grips. On the right side the Eastern and Western Grips are illustrated: note that the hand of the players is in the same position while the inclination of the racket changes. Other grips are described in the text. The blue hexagons are positioned in critical areas (base knuckle and heel pad).