Electronic line calling systems are operated under rules that limit the number of challenges that can be issued. When these systems were first unveiled, processing the challenges was considerably slower than current systems. The philosophy behind the limits was to allow players a reasonable number of challenges without excessively slowing play.
The limits on challenges only applies to unsuccessful appeals. If the officiated line calls are excessively bad, the player can challenge as many calls as they want… but only if they are wrong no more than three times.
Each player (team) is allowed three (3) unsuccessful appeals per set, plus one (1) additional appeal in the tie-break. For matches with advantage sets, players (teams) will start again with a maximum of 3 unsuccessful appeals at 6 games all and every 12 games thereafter. For matches with match tie- break, the match tie-break counts as a new set and each player (team) starts with three (3) appeals. Players (teams) will have an unlimited number of successful appeals.
Appendix IV, Electronic Review Procedures, ITF Rules of Tennis, USTA Friend at Court
Organizers of the 2015 US Open sent a letter to players that year outlining the procedures for electronic line calling systems implemented during that tournament. Based on that artifact, one of the primary concerns with electronic challenge systems was potential impact on the pace of play. In fact, the requirement for players to issue challenges immediately and without delay was peppered throughout the document in bold font.
Current line calling systems are considerably faster than the ones that the electronic review procedures in the ITF Rules of Tennis were based on. It is possible that at some point in the future that the limitations could be removed entirely.
In fact, earlier this year the Mutua Madrid Open experimented with allowing players unlimited challenges. Chaos did not ensue. It didn’t seem to have a material impact on either the number of challenges that players ultimately issued at that event. Consequently, the pace of play was not impacted.
It is not far fetched to imagine that limitations on the number of challenges may one day disappear from the rules.
- Friend at Court: The Handbook of Tennis Rules and Regulations, USTA, 2022
- Electronic Review Procedures Message to Players, US Open 2015.
