The Women’s Tennis Association says it takes “full responsibility” for not telling players there were microphones on practice courts after private comments Jessica Pegula made to her coach about fellow player Mirra Andreeva were live-streamed.
The session at Indian Wells, California, was streamed by the WTA before its Tour Finals start on Sunday.
In a private conversation with her coach Mark Knowles, world number five Pegula described Andreeva as “a diva”.
The American could also be heard saying the French Open champion “needs to be humbled” and her coach Conchita Martinez encourages her behaviour.
Pegula’s agent, Chris McCormack, said she had been “completely unaware” the conversation could be heard by courtside microphones, “let alone live-streamed to the public”.
“Naturally it’s been an unfortunate situation for everyone involved,” McCormack told BBC Sport.
“Jess has since been in direct contact with those involved, which she felt was important to do personally rather than through the media.”
YouTube streams of Wednesday’s practice sessions at Indian Wells have since been removed by the WTA, but the footage had already been shared on social media.
It is understood the microphones were only intended to capture the sounds of rallies and not any conversations on court, and there will be no audio on future videos.
“The WTA takes full responsibility for failing to inform our players and their teams that microphones, in place to give fans a livestream of the players’ practice, were active on the courts at the WTA Finals,” a statement read.
“We sincerely apologise for failing to meet our responsibility to ensure players and coaches were properly informed.”
Pegula, who is a member of the WTA players’ council, also praised Andreeva, saying the world number three is “wonderful” and “smart”.
The season-ending WTA Finals, being held at Indian Wells for the first time, run until 15 November.
Pegula’s representative and the WTA have been approached for comment.
In a separate incident, world number one Elena Rybakina appeared to have an angry exchange with her coach before a practice session with Wimbledon champion Linda Noskova.
