Electronic Line Calling was at the center of controversy once again on clay courts, as the match between Damir Dzumhur and Matteo Arnaldi at the Croatia Open sparked a dispute over a technology error. The match between the two was on a knife-edge in the first-set tiebreak, with the Bosnian having taken a 4-1 lead.

However, that is when things went pear-shaped as Arnaldi hit an ace, taking the Italian to 4-2. Even though the ELC had called the ball in by a fair margin, the naked eye could spot the mark of the ball outside the service line. This is where Dzumhur expressed his irritation and had an angry outburst at the chair umpire. He was heard saying, “I’m not playing anymore,” and “Be honest once in your life.”

The Bosnian’s frustrations are justified, as he had come back from a 2-5 deficit in the first set and taken it to a tiebreak while saving a set point. However, he kept his cool and won the first-set tiebreak, eventually winning a three-set battle just under four hours.

Unlike hard or grass courts, the unique quality of the clay courts is that the top layer of the surface constantly shifts as players run and slide on it. Even when the ball lands on the surface, it kicks up some clay, which often means the ELC cameras cannot properly track the ball’s actual landing point. The sidelines, which are on a clay court, are often cement strips because paint cannot be used on the red dirt, which can cause the clay to stick to the lines and potentially mess up the ELC’s tracking data.

Dzumhur is not the only one who has been on the wrong side of an iffy ELC call this clay season. During the Madrid Open, the ever-calm Elena Rybakina had a verbal spat with the chair umpire when the ELC called in her opponent Zheng Qinwen’s serve as an ace. A physical mark told the opposite story, supporting the Kazakh player’s claims. The ELC’s presence also limits the chair umpire’s authority, as they cannot overturn an ELC call, even in cases of clear discrepancy.

Incidentally, even though all the Tour-level events have adopted the ELC, the biggest clay-court event of all still uses the traditional method to decide line calls, which has its own set of difficulties.

The French Open Is the Only Clay-Court Event Not to Use ELC

The French Open is the last clay-court event on Tour that does not use ELC, relying instead on line judges’ calls, with the chair umpire’s decision in case of a disputed call. The player cannot challenge an electronic replay of the point, but they can ask the chair umpire to inspect the call, which the latter does by looking at the mark the ball left on the surface. Ironically, however, most Roland Garros broadcasters include the ELC in their coverage, which shows ball tracking for the audience, but the chair umpire cannot do anything even if the on-court call is incorrect.

Finding the exact mark when the ball hits the surface is the chair umpire’s challenge, which is similar to ELC. With players sliding and running on the clay, there are a lot of additional marks as well, which the chair umpire has to separate from the one in question. Like the ELC, even chair umpires are not 100 percent foolproof in their decisions, as seen in this year’s match between Casper Ruud and Joao Fonseca. With the Norwegian leading 8-7 in the second-set tiebreak, the Brazilian’s forehand was called out by a member of the audience. Hearing that call, Ruud understandably stopped the point, but the chair umpire came down and adjudicated the ball to be in, which was crucial for Fonseca, who won the second set and had a two-sets-to-love lead.

A similar issue took place at the French Open in 2024 as well, with Alexander Zverev getting the short end of the stick of an umpire-made line call in his final against Carlos Alcaraz. Despite the complaints, the Roland Garros organizers have emphasized maintaining the tradition of employing line judges while citing deficiencies in the ELC system.