Will This Be the Last French Open With Only Human Eyes Minding the Lines?

In the nearly 100 years they have been playing tennis at Roland Garros, the ritual has not altered.

A ball lands close to a line. A call is made. A player expresses doubt. A chair umpire descends to inspect the ball mark on the red clay and renders final judgment, often with the umpire and the player both hunched over the evidence in the soil like archaeologists.

But like so much in our world, the French Open and other clay-court tournaments are facing change.

Tour-level events held on hardcourts and grass already use electronic line calling in some form, including all three of the other Grand Slam events: the Australian Open, Wimbledon and the United States Open.

Clay events are the last holdouts in large part because the balls leave behind marks that allow line calls to be verified without video. There are no such marks on grass, and they are much less definitive on hard courts, if they exist at all.

But technology is on the march. FoxTenn, a Spanish line-calling system, has received approval from the men’s and women’s tours for a trial use on clay. Hawk-Eye, long the leading system in tennis, is seeking similar approval, and a version has even been used in some tournaments to eliminate human line judges completely.

The players, particularly young ones raised with the internet and ubiquitous screens, are increasingly clamoring for the automation.

“We should start using Hawk-Eye for the clay-court tournaments as well, because then we don’t need to have all these arguments with umpires,” said Casper Ruud, a 21-year-old Norwegian who disputed two line calls during his third-round loss to Dominic Thiem at the French Open last week.

Some players, like Marton Fucsovics, have gone so far as to take pictures of questionable marks with their phones, a practice that the tennis authorities have discouraged.

Their resistance may soon be irrelevant.

“I think the toothpaste is out of the tube,” said Gayle David Bradshaw, a former ATP Tour vice president for rules and competition who retired in 2019. “My position as an official has always been that if there’s a way to make it better for our athletes, we should do it.”

Bradshaw attended a trial for FoxTenn at a satellite tournament on clay in Barcelona last year.

“There were only, like, three times the whole tournament a player kind of looked funny at the call and the mark,” he said, “and I think the majority of the players were positive.”

In February, the Rio Open became the first main men’s tour event on clay to try FoxTenn.

The system was also used at a Fed Cup match on clay between the Netherlands and Belarus in February, Javier Simon, chief executive of FoxTenn, said in a telephone interview from Barcelona on Wednesday.

It will get trials in more events, including a Masters 1000 event in Madrid next year.

“For the first time, we have been looking at clay and understanding that there are a lot of errors the human eye is able to create on this surface,” Simon said. “The myth of the mark on the court finally has been broken.”

For the moment, the French Open audience, if not the tournament itself, has a foot in both the traditional and the electronic worlds.

Television networks covering the French Open have used the Hawk-Eye technology for more than a decade. They regularly show images from the system when umpires’ rulings are contested, even though the system’s rulings are not official.

On Friday, during the men’s singles semifinal between Diego Schwartzman and Rafael Nadal, Schwartzman hit a shot early in the second set that landed near a sideline. It was called out, and the chair umpire, Aurelie Tourte, soon confirmed it after closely examining the mark. Schwartzman was skeptical. Even Nadal took a long second look at the mark, and a Hawk-Eye replay on television later showed that the shot had just clipped the line.

Moments like that invariably undermine faith in the official rulings, but some analysts question the trustworthiness of the technology versus that of a veteran umpire, particularly because clay, unlike hardcourts, is an ever-shifting surface. Fluctuations, however slight, could produce inaccurate images from Hawk-Eye, which relies on tracking cameras that project the flight of the ball.

“There’s an issue with it being a moving surface,” said Darren Cahill, the coach of Simona Halep, the 2018 French Open champion.

Hawk-Eye officials declined to comment on their clay-court system, citing the sensitivity of ongoing negotiations, but they indicated that the system being used for television at this year’s French Open is what the company would use for electronic line-calling on clay, if approved.

For now, frustration reigns among both viewers and players.

Ruud contested two calls made during his loss to Thiem. Friends later sent Ruud a photograph they had taken from the television coverage, which showed that the Hawk-Eye replay agreed with him.

“It’s a bit strange that they have the Hawk-Eye available here, but they only show it for the TV,” Ruud said, “and I don’t understand why we can’t use it, to be honest.”

FoxTenn was in negotiations with Roland Garros two years ago, Simon said, but no agreement has been reached. Asked about the possibilities for 2021, he said, “Important things are going to happen.”

FoxTenn uses a system that differs from its rival’s in a way that reduces the margin of error, Simon said. Instead of projecting where the ball will land, he said, FoxTenn captures images of the precise moment the ball strikes the ground.

“It is not a 3-D re-creation; we give the real image,” Simon said. “We see the surface of the court how it is, even if it has moved or just moved.”

This year, the U.S. Open became the first Grand Slam event to use almost exclusively electronic line calling, eliminating line umpires on all but two of its courts. Initial feedback was positive, according to Stacey Allaster, the tournament director, but the U.S. Open has yet to commit to using the same system in 2021.

Electronic line judging would most likely eliminate one current issue: umpires examining the wrong ball mark on the clay, which is a frequent source of tension with players. But if there is a switch to electronic calls, players will still be able to see the mark on clay, and it will not always match what technology records.

“The ball mark can be larger or smaller than the true contact area depending on the amount of clay, humidity of clay, speed of the ball, direction of travel, etc.,” said Stuart Miller, executive director of the science and technical department at the International Tennis Federation.

In other words, players who now argue that the Hawk-Eye image supports them could someday be insisting that the mark proves their point instead. Whatever it takes to win any given point.

“I know you have an issue at the moment, but you’ll have an issue the other way as well,” Cahill said.

“We have a system on clay we have used forever,” he said, adding that chair umpires deserve some credit. “They’ve been doing their jobs for the last 100 years, so I think on clay the system we have at the moment is a pretty good system. If we can better it, I have no problem with that, but you need to prove to me we have a better option.”