Add U.S. Open champion Dominic Thiem and the man he beat at the French Open on Friday, No. 28 seed Casper Ruud, to the growing chorus of players who think electronic line-calling should come to clay-court tennis.

It’s not a new idea. And there are questions about the accuracy of that sort of system on clay, where the red dust shifts, making it harder for the machine to be as right as it can be on hard courts.

Still, just in the past couple of days at Roland Garros, top-10 seeds Stefanos Tsitsipas and Denis Shapovalov have raised the issue, as did 2018 semifinalist Marco Checcinato, who grumbled about it during the third set of his third-round loss Friday.

Empty seats from the background as Norway's Casper Ruud plays a shot against Austria's Dominic Thiem in the third round match of the French Open tennis tournament at the Roland Garros stadium in Paris, France, Friday, Oct. 2, 2020. (AP PhotoMichel Euler)

Empty seats from the background as Norway's Casper Ruud plays a shot against Austria's Dominic Thiem in the third round match of the French Open tennis tournament at the Roland Garros stadium in Paris, France, Friday, Oct. 2, 2020. (AP PhotoMichel Euler)

“Today in my match there was a mistake -- in my favor actually,” two-time French Open runner-up Thiem said after beating Ruud 6-4, 6-3, 6-1. “Casper showed me the mark on his phone after the match.”

Thiem played at a tournament in Brazil where a system fine-tuned for use on clay, specifically, was tested.

“There were not any issues,” he said. “So I hope that next year, we will have it in every clay-court tournament.”

Romania's Simona Halep flashes a thumbs up after winning her third round match of the French Open tennis tournament against Amanda Anisimova of the U.S. in two sets, 6-0, 6-1, at the Roland Garros stadium in Paris, France, Friday, Oct. 2, 2020. (AP PhotoMichel Euler)

Romania's Simona Halep flashes a thumbs up after winning her third round match of the French Open tennis tournament against Amanda Anisimova of the U.S. in two sets, 6-0, 6-1, at the Roland Garros stadium in Paris, France, Friday, Oct. 2, 2020. (AP PhotoMichel Euler)

After Ruud disputed a couple of calls with the chair umpire, some buddies back home in Norway who were watching the match took a picture of one of the ball marks on the TV sceen and sent it to his phone.

“It was,” he insisted, “quite clearly out.”

HALEP TURNS IT AROUND

Poland's Iga Swiatek plays a shot against Canada's Eugenie Bouchard in the third round match of the French Open tennis tournament at the Roland Garros stadium in Paris, France, Friday, Oct. 2, 2020. (AP PhotoMichel Euler)

Poland's Iga Swiatek plays a shot against Canada's Eugenie Bouchard in the third round match of the French Open tennis tournament at the Roland Garros stadium in Paris, France, Friday, Oct. 2, 2020. (AP PhotoMichel Euler)

A year ago, Simona Halep’s French Open title defense ended in Court Philippe Chatrier with a lopsided loss to American teenager Amanda Anisimova in the quarterfinals. They met again Friday -- same tournament, same stadium, similar scoreline -- but this time it was Halep who dominated, winning 6-0, 6-1 in less than an hour.

“I was playing really bad,” said Anisimova, a fair assessment given that she made 32 unforced errors, 25 more than the No. 1-seeded Halep. “It’s been one of the worst matches I have played in a while. I was just making mistakes all over the place.”

The key, believe or not, might very well have been the second game.

Taylor Fritz of the U.S. plays a shot against Tomas Machac of the Czech Republic in the first round match of the French Open tennis tournament at the Roland Garros stadium in Paris, France, Sunday, Sept. 27, 2020. (AP PhotoMichel Euler)

Taylor Fritz of the U.S. plays a shot against Tomas Machac of the Czech Republic in the first round match of the French Open tennis tournament at the Roland Garros stadium in Paris, France, Sunday, Sept. 27, 2020. (AP PhotoMichel Euler)

“Very important,” Halep called it.

She double-faulted twice, helping the 25th-seeded Anisimova accumulate five break points.

But Anisimova couldn’t convert any of those chances and never held another break point.

Now comes another rematch for Halep, against another 19-year-old: Her fourth-round opponent is Iga Swiatek.

In 2019, Halep won their fourth-round match in Paris 6-1, 6-0.

“I know for sure that my game is better,” Swiatek said, “so hopefully this match is going to be longer than 40 minutes.”

BREAKING THE TIE

Thirty minutes; 36 points.

Lorenzo Sonego and 27th-seeded American Taylor Fritz engaged in quite a tiebreaker Friday.

Each held more than a half-dozen sets points. It finally ended when Sonego took the last two points with drop shots and ended the match, winning 7-6 (5), 6-3, 7-6 (17) to get to the fourth round at a Grand Slam tournament for the first time.

“I’m going to be up all night,” Fritz said, “thinking about what I could have done different.”

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