Wimbledon champion Marketa Vondrousova on Monday joined world No 1 Aryna Sabalenka in hitting out at the WTA and the state of the court at the season-ending Finals in Cancun.
Sabalenka on Sunday said she felt "disrespected" by the WTA, the governing body for women's tennis, saying that the hastily built court in the Mexican resort was "not safe".
The Czech Republic's Vondrousova agreed, writing on Instagram: "My first WTA Finals is not at all what I imagined.
"We work hard all year to get to the Finals and in the end it's just a disappointment."
Vondrousova, who lost 7-6 (7/3), 6-0 to Iga Swiatek in her opening match on Monday, posted alongside the comments a clip of the ball failing to bounce properly on the court during a rally.
"Stadium is not at all ready for the matches and to me it feels like the people from WTA are absolutely not interested in how we – who are supposed to play on that court – feel," wrote the 24-year-old.
"We do not feel that anyone listens to us and is interested in our opinion.
"Very sad."
Cancun was only confirmed as the host city of the prestigious championship on September 7 after Saudi Arabia had reportedly been lined up to stage the event.
That possibility sparked criticism from US legends Martina Navratilova and Chris Evert among others.
Instead, the tournament has returned to Mexico for the second time in three years, after Guadalajara hosted in 2021.