Women's Tennis Association chief Valerie Camillo apologised on Friday after a courtside microphone captured US star Jessica Pegula making disparaging comments about rival Mirra Andreeva.
Pegula was plunged into controversy after her conversation with coach Mark Knowles on a practice court at Indian Wells in California was broadcast on a WTA YouTube livestream of the session.
In the exchange, Pegula can be heard describing 19-year-old Russian Andreeva as a "diva".
World No 4 Pegula was also heard criticizing Andreeva's coach, former Wimbledon champion Conchita Martinez, for not addressing French Open champion Andreeva's behaviour.
Speaking ahead of Sunday's opening matches of the WTA Finals, WTA chairperson Camillo blamed the controversy on "several breakdowns in our execution of the livestream given our own policies and procedures."
"I want to apologise on behalf of the entire WTA for these occurrences," Camillo said at a press conference.
"The WTA is sensitive to player privacy and has policies and procedures in place to balance players' needs for safe spaces with opportunities to bring fans closer to the game.
"There was a lack of advanced notice and clear signage to assist players about the recording equipment operating in the area," she added, confirming that all audio recording equipment in practice areas had since been removed.
'AMBIENT SOUND'
Camillo said microphones had been installed on practice courts to pick up "ambient sound" – such as the noise of balls being struck – rather than conversations between players and coaches.
"So clearly there was a failure in our technical execution and monitoring," Camillo said, before directly apologising to Pegula and Knowles.
"I want to specifically apologise to Jessica Pegula and Mark Knowles," Camillo said.
"What happened was regrettable and unacceptable. Jess is one of the WTA's best advocates and biggest stars. She does not deserve this distraction."
The WTA Finals gets underway on Sunday, with the top eight women's singles players divided into two round-robin groups of four before advancing to the knockout rounds.