After tennis star Serena Williams wore a black catsuit at this year’s French Open tournament, the country’s tennis officials announced that they would be enforcing a dress code for subsequent tournaments, according to NPR. French Tennis Federation President Bernard Giudicelli specifically called out Williams’ catsuit in an interview with Tennis magazine. “It will no longer be accepted. One must respect the game and the place,” he said. Other tennis tournaments, like Wimbledon, have strict dress codes—but Giudicelli said the French Open’s guidelines would not be as restrictive as the U.K. tournament’s “all-white” rule. Williams told reporters in May that she felt like a “warrior princess” in the catsuit, and said pants were helpful to wear while she was playing to “keep the blood circulation going.” After giving birth to her daughter last year, she suffered from blood clots in her lungs and has since had “a lot of problems” with clots.