Immediate disruption and long-term tactical adaptation after the three-point line extension in EuroLeague basketball:...

This study examined the immediate disruption and long-term tactical adaptation associated with the 2010-2011 extension of the three-point line in EuroLeague basketball. Shot-location, play-by-play and box-score data were analysed across 19 seasons, from 2007-2008 to 2025-2026. The final sample comprised 5,034 games, 10,068 team-game observations, 614,442 field-goal attempts and 233,323 three-point attempts. The primary outcome was three-point attempts per 100 estimated possessions; secondary outcomes included three-point attempt rate, three-point accuracy and median three-point distance. Segmented regression models estimated pre-change trends, immediate level changes and post-change trend changes, with estimates interpreted cautiously because only three pre-change seasons were available. Three-point volume decreased from 29.4 attempts per 100 possessions before the extension to 27.1 in 2010-2011. The model estimated an immediate reduction of -2.47 attempts per 100 possessions (95% CI [-3.62, -1.32], p < 0.001). Three-point accuracy declined descriptively in the first post-change season, but no independent immediate step-change was supported. Median three-point distance increased after the reform. Overall, the rule change was associated with a temporary reduction in three-point volume followed by long-term recovery and expansion.