Same formation, different styles: An exploratory study of clustering playing style of teams in 4-3-3 formation in elite soccer

This study examined whether teams using identical formations display similar playing styles by integrating Phase of Play (PoP) indicators with clustering and explainable machine learning. Ninety-three observations from teams employing a 4-3-3 formation in the FIFA World Cup 2022 (n = 58) and FIFA Club World Cup 2025 (n = 35) were analyzed. K-means clustering identified distinct styles, while XGBoost with SHapley Additive exPlanations (SHAP) interpreted key differentiators. Two contrasting styles emerged despite identical formations: a possession-oriented and a defending-oriented style. SHAP revealed attacking transition and both opposed and unopposed build-up as decisive in-possession indicators, and low block and high press as main out-of-possession factors. The possession-oriented cluster was characterized by structured build-up play, higher possession, total passes, pass completion ( p  < 0.001, large), and more defensive line breaks ( p  < 0.01, moderate). The defending-oriented cluster demonstrated deeper defensive organization, with greater low-block, more pushing-on-into-pressing actions and defensive pressures ( p  < 0.001, moderate), and longer ball recovery time ( p  < 0.001, large). These findings show that teams sharing the same formation can differ substantially in style, emphasizing the limitations of formation-based analysis and the value of PoP indicators for understanding functional behaviors in elite soccer.