Yulia Putintseva ignored a ball girl as she tossed balls at her while on serve during the US Open on Sunday, 1 September.
The Russian-born player, who represents Kazakhstan, allowed the first two balls to bounce off her while appearing to stare directly at the ball girl, before catching the third and turning away.
Feliciano Lopez, the former Spanish player and director of the Madrid Open tournament, said Putintseva had humiliated the ball girl.
Putintseva later said she was “p***ed off” with how she was playing.
“I want to apologise to the ball girl for the way I was, when she was giving me balls,” the player said on her Instagram story.