Electronic Line Calling on the Fritz

A much-publicized electronic line calling (ELC) error during a match between Taylor Fritz and Brandon Nakashima at the Cincinnati Open a couple of weeks ago generated a lot of outraged public discourse. The incident also allegedly resulted in an ATP rules change, but we’ll get back to that. To summarize what happened, the ELC system missed an obvious “out” ball, and the point continued for several more shots before an off-court Hawk-Eye official stopped play. The chair umpire ruled that a “let” would be played because Fritz did not immediately stop the point.

In case you missed it or have come to this page in the future for a refresher on what transpired, the Guardian’s YouTube channel published a good summary of the incident.

The ATP Official Rulebook is the authoritative source for this situation. This is an “edge case” in the rules that explains the officiating decisions but also defies common sense. When human linespeople are in use and backed up by ELC systems for challenges, a player is required to immediately stop the point to challenge a call. However, when ELC systems are used for all the line calling, as was the case at the Cincinnati Open, a player can ask to see close calls only after the point ends.

Had Fritz elected to immediately stop that point and the ELC glitch was a misread of the ball rather than a failure to annunciate the call, he would have lost the point even though the ball appeared to be out. Consequently, players are coached to never stop the point when they doubt a line call under those circumstances.

If the Live ELC system fails to make a call, the call shall be made by the Chair Umpire. If the Chair Umpire is unable to determine if the ball was in or out, then the point shall be replayed. This protocol applies only to point ending shots or in the case when a player stops play. In the case where there is no call, and the player stops play, the umpire shall call for the shot to be displayed on the video board for confirmation.
ATP Official Rulebook, VII.B.4, August 2, 2024

Players, fans, and commentators decried the decision to play a let rather than awarding the point to Fritz. The common sense logic is that once a ball is out, the point is over regardless of what subsequently happened. This incident apparently prompted the ATP to announce a new rule to that effect. In the future, if the Review Official determines that a ball was out earlier in the point not called by the system, the missed “out” call will stand rather than playing a let.

Here is where the saga takes a strange twist. Last week, I visited the ATP site to see if this new rule was already reflected in the ATP rulebook. I was initially reassured to find out that it was. However, the revision date was August 2, 2024, which is before the Fritz-Nakashima match took place on August 13. That implied that the update was already in place, raising questions over how the ATP communicates rules updates to officials. It would also mean that an officiating error was made rather than a correct interpretation against an edge-case scenario.

When I revisited the ATP site this week to download the August 2 version of the Rulebook with plans to reprint the new rule, it was no longer in the document. The date on the Rulebook currently posted to the ATP site is still August 2. In other words, the new rule that I saw pertaining to this situation was temporarily inserted and then removed. I wish I had downloaded it when I reviewed it last week.

Configuration management is an important technical concept at my day job, where I work with software systems. It is equally important for organizations that publish rulebooks. In tennis, it is essential to have clear guidance for what rules apply when a match occurs. Configuration Management documents the inflection point between what would be an officiating error and the episode that prompted a rules update.

In any case, this post was originally going to end with the new rule that had been added rather than anticipating a future update. In the interim, I can confirm that language consistent with the ATP announcement of this new “common sense” rule is likely forthcoming… because I already saw it.