Ibtehal Alkhawaldeh https://czasopisma.ujd.edu.pl/index.php/sport/article/view/1848/1484 Fatigue in muscles is a reason for the low skill performance of soccer players so this study sought to find out the effect of the quadriceps muscle fatigue resulting from an isotonic contrac-tion on some kinematic variables and the accuracy of soccer players’ execution of the corner kick. A test for the accuracy of the corner kick and the leg press exercise was used on a sample of [8] international soccer players, and their means were as follows: age: 26.8 ± 2.3 years, height: 174 ± 12cm, mass: 71 ± 6kg, training age: 14.6 ± 1.8 years. The performance of the corner kick test was videotaped by three cameras and Kinovea program for kinematic analysis was used. The re-sults showed a negative effect of the quadriceps muscle fatigue after isotonic contractions on kinematic variables and on the accuracy of corner kicks. The study results point to the necessity of enhancing the ability of soccer players in terms of endurance of muscle strength in the quadri-ceps muscle to the highest possible extent due to the importance of that element in their skillful performance, including the accuracy of the implementation of corner kicks.