This move is originally Kirihara Akaya 's The Knuckle Serve is a more powerful version of the Kick Serve and the Twist Serve. The user presses the ball between his fingers (more precisely, his knuckles. Hence the name.) and then throws the ball up into the air, which creates an unusual spin on the ball. When the ball bounces, it goes straight for the opponent's body with high speed and destructive power. The direction can only be decided and determined by its user. Fuji (anime only) also uses this move to take revenge for the injuries Tachibana sustained due to Akaya's violence in their match.