Validating and identifying KPIs in ATP/WTA hard court tennis match play (2019–2023) using the PWOL method

The study provided further validity for the use of the PWOL (percentage of matches which the winner outscored the loser) method within elite hard-court tennis. Over half of the ATP/WTA competitive calendar (January-March and August-November) is played on hard courts so is an important progression. Data from 810 men's and 586 women's hard-court matches across Grand Slams and ATP/WTA World Tours (i.e. Masters, 500s and 250s) between 2019 and 2023 was used for analysis. PWOL was validated alongside two traditionally used statistical methods (paired t-test, point-biserial correlation). Very high agreement between all approaches was shown using Spearman's correlation analysis for both men and women (>0.97). The study further identified the indicators most related to winning performance, identifying baseline points won, first serve points won, points won of 0-4 rally length and Winners:UE Ratio to be most strongly associated with success, whilst forced errors were most associated with losing. Ball three indicators lacked association with match outcome, suggesting any major focus training ‘one-two punches’ on serve should be approached with caution. PWOL has proven to be a valid method for assessing success in elite hard-court tennis (offering potential for wider sports application) to ultimately aid coach decision-making.