A closer look at the prevalence of time rule violations and the inter-point time in men’s Grand Slam tennis

Paragraph 29a of the official ITF Rules of Tennis sets a limit of 20 seconds for the time players can take between points. This study investigates the prevalence of violations of this rule, the corresponding umpire’s behavior and factors that influence the inter-point time in general. Regression analysis of 3475 serves of the 2016 Australian Open Men’s Singles tournament showed an autonomous influence on the variance of the inter-point for the serving player, the duration of the previous rally, the service game, the current scoring streak and the importance of the point. The average time between points was 21.5 seconds and time rule violations were found for 58.5% of the serves. Only two (0.1%) of these rule violations were penalized by the umpire, with the punished incidents occurring after 23.5 and 25.6 seconds, representing the 65.9th and the 78.1th percentile respectively of the detected inter-point times. Thus, we concluded that the current rule is not just applied too lax but also capriciously. Based on the detected influences on the time between points we suggest various adaptions of the rule, e.g. a dynamic time limit based on the duration of the previous rally, as well as ways to improve the enforcement of the rule, e.g. technological officiating aids.