The Faculty of Physical Education and Sports Sciences at the University of Karbala discussed a master’s thesis entitled “Differentiation of skillful performance and some cognitive and biokinetic abilities as a function of selecting defensive players in football under 17 years old.”

The thesis presented by the student (Ali Sobhi Assi) sought to identify the level of skillful performance and cognitive and biokinetic abilities as a function of selecting defensive players with a soccer ball under 17 years old, and to identify discriminatory indications of skillful performance and cognitive and biokinetic abilities as a function of selecting defensive players with a soccer ball under 17 years old, as well as identifying Selection of emerging defensive players in terms of effect sizes for skillful performance and some cognitive and biokinetic abilities.

The researcher adopted the descriptive method in the survey method, and the research community included the players of Karbala governorate clubs for the youth category, while the researcher applied the study to a sample of 190 players.

The thesis recommended the need to adopt the results of the current study as an indicator for the classification of emerging defensive players and the necessity of conducting studies that include the variables of the current study on other sports because of their impact and importance in classification.