Madrid Open organisers have apologised for not allowing the women's doubles finalists to speak on court following Sunday's match.
The WTA are reportedly investigating the various issues raised regarding the treatment of its players at the Caja Magica last week, and the tournament's chief executive Gerard Tsobanian has now issued a public apology.
The convention is for the runners-up and winners to address the crowd following finals, and champions Victoria Azarenka and Beatriz Haddad Maia and beaten finalists Coco Gauff and Jessica Pegula were shocked to be denied the opportunity.
Tsobanian wrote on Twitter: "We sincerely apologise to all the players and fans who expect more of the Mutua Madrid Open tournament.
"Not giving our women's doubles finalists the chance to address their fans at the end of the match was unacceptable and we have apologised directly to Victoria, Beatriz, Coco and Jessica.
"We are working internally and with the WTA to review our protocols and are committed to improving our process moving forward. We made a mistake and this will not ever happen again."
There was also criticism of the revealing outfits worn by model ball girls on the main court as well as the way the tournament celebrated the birthday of male champion Carlos Alcaraz compared to women's singles winner Aryna Sabalenka.
They share a birthday on May 5 but, while Alcaraz was presented with a huge cake on court after his semi-final, Sabalenka, who was not playing that day, was given a much more modest confection backstage.
It is not the first time the Madrid Open, which is now owned by leading agency IMG, has been accused of favouring men over women, and Azarenka tweeted in response to pictures of two cakes: "Couldn't be more accurate on the treatment."
In their speeches after the women's final, Sabalenka made a joke about the cakes while runner-up Iga Swiatek made clear her unhappiness with being made to play after midnight.
That appeared to be the final straw for tournament director Feliciano Lopez, who had hit back at criticism over the cakes on Twitter.
The WTA has not made any public comment on the matter but it is understood it does not agree with the decisions that were made and is looking into events.
Speaking ahead of the Italian Open in Rome this week, Pegula told reporters: "I've never heard of that (not being allowed to speak) in my life.
"I don't know what century everyone was living in when they made that decision or how they actually had a conversation and decided, like, 'Wow, this is a great decision we're going to do and there's going to be no backlash against this'."
