French Open organisers had “no grounds to penalise” Maria Sharapova by denying her a wildcard entry to the tournament, says the Women’s Tennis Association.
The Russian, 30, was ranked too low to gain direct entry as she continues her return from a 15-month drugs ban.
The French Tennis Federation (FFT) chose not to hand Sharapova a wildcard to “protect” the sport’s standards.
“I don’t agree with the basis for their decision. She has complied with the sanction,” said WTA chief Steve Simon.
“There are no grounds to penalise any player beyond the sanctions set forth in the final decisions resolving these matters.”
Two-time French Open winner Sharapova needed a wildcard, which are awarded at the discretion of tournament organisers, to play in either the main draw or the qualifying tournament.