Swiatek said on Wednesday she did not like the balls set to be used at the US Grand Slam, which are lighter for women than those for men, adding that the female players make more mistakes while playing with them, and she doubted it was "nice to watch visually".

"Very much agree," Spain's Badosa said, hailing the words of the Polish world number one on Instagram on Friday, placing her comments over a screenshot of Swiatek's statement.

"Very unfavourable conditions for the players and for the spectacle," she wrote, even adding a poop emoji for emphasis.

"Then we complain that there are a lot of errors and there's a loss of tactics and intelligence on points. (While what we deal with is) faster courts and balls impossible to control."

The 2022 US Open will begin on Aug. 29 and will end on Sept. 11.