Much research has been conducted to understand how anxiety can affect sports performance, both in practice and in development. It is known that exercise is associated with high levels of stress and threat potential, and the application and application of a number of psychological strategies can be beneficial in managing anxiety. The article is devoted to the evaluation of the level of dihydropyrimidinase-like protein 2 (DBZ2) in platelets and saliva of basketball players before the competition and the level of natural autoantibodies against DBZ2 in blood serum. Instead of control, samples of blood and saliva from those athletes in normal condition were used. The levels of DBZ2 and natural autoantibodies against DBZ2 were determined by indirect immuno-enzymatic assay on polystyrene tablets with a moderate level of adsorption. The results of the research showed a significant decrease in the level of natural autoantibodies against DBZ2 in the serum of the athletes before the competition (p < 0.01) and no changes of DBZ2 in their platelets and saliva. Based on the evidence obtained in previous years, our results allow us to conclude that athletes reflect similar changes in the level of DBZ2 in the subcortical regions of the brain and indicate an increase in their level of aggression before competition.