ABSTRACT

The game system is defined as the general form in which players' attacking and defensive actions are organised, by establishing a precise arrangement of certain tasks (positions and field coverage) and certain principles of co-operation between them. The game system is the basic structure of collective team tactics (Teodoresca, 1965) In soccer, these arrangements refer most often to a formal distribution of positions and field coverage among various players, as expressed in team structure. These are described in systems such as WM, 4–2–4, and 4–4–2 (Frantz, 1975; Talaga, 1977; Morris, 1981), which illustrate with more or less precision the strategy the trainer has chosen. Quite obviously, a system which objectively quantifies the movements of performers within the game situation would be a valuable tool to aid the coach in evaluating team performance.