Coco Gauff was not pleased with the chair umpire’s decision against her during a French Open semifinal loss to Iga Swiatek on Thursday — and made it apparent to the official.

Gauff also believes that tennis should progress into the 21st century and use video replay technology at all events, as many other sports do. “At this point, it’s almost ridiculous that we don’t have it,” she stated. “There are so many decisions made, and it kills as a player to go back or watch online and realise you were perfectly correct. And the question is, “What does that give you in that moment?”

The 20-year-old American, who won the U.S. Open in September for her maiden Grand Slam title, questioned chair umpire Aurélie Tourte’s ruling early in Swiatek’s 6-2, 6-4 victory. Swiatek hit a serve that was initially called out just as Gauff was swinging for a return that landed out. The call on the serve was reversed to “In,” and Tourte gave the point to Swiatek; Gauff argued that this was unfair because she believed she had been affected by the original “Out” call. “I have the right to finish my swing,” Gauff explained. Tourte’s response? “It had no effect on the shot,” she explained.

Gauff then told Tourte she was wrong and “should be ashamed.”

“It’s a Grand Slam semifinal,” Gauff told the official. “Know the rules of the game.”

Tourte did not budge.

When action resumed, Gauff walked back behind the baseline and used her wrist bands to wipe at her eyes

Every point matters against anybody, but especially against her. I think it was just one of those moments, but I overcame it. I obviously won that game,” Gauff said. “I usually don’t get too frustrated with decisions like that, but I think it was just a combination of everything going on in the moment.”

Gauff did break Swiatek for the only time in the match right then for a 3-1 lead in the set. But Swiatek would take five of the next six games to reach another final at Roland Garros, where she is seeking a third consecutive trophy and fourth in five years.

As for the larger issue of whether Tourte should have been able to examine some sort of replay to figure out whether the line judge’s shout did affect things, Gauff had zero doubt about her stance.

“I think tennis is the only sport where not only we don’t have the (video replay) system … (and) in other sports, there’s usually multiple refs making a decision,” Gauff said, noting that the U.S. Open did add replays for certain calls last year. “I definitely think, as a sport, we have to evolve. And have the technology. They’re showing it on TV, so I don’t get why the player can’t see it.”