World No 1 Aryna Sabalenka made a superb start to the season-ending WTA Finals by smashing Maria Sakkari 6-0, 6-1 in her opening match in Mexico.
But instead of celebrating her comprehensive victory, the Belarusian voiced her frustration at the tournament's organisation and criticised the lack of practise time on the court.
The 25-year-old Australian Open champion fired six aces and 17 winners while saving all five break points she faced to dispatch Greece's Sakkari in just 74 minutes in Cancun.
The venue for the finals was only confirmed in early September after the WTA and Saudi Arabia failed to reach an agreement and the construction of the court was only completed in the days before Sunday's start.
“I am very disappointed with the WTA and the experience so far at the WTA Finals,” said Sabalenka. “This is not the level of organisation we expect for the Finals.
“To be honest, I don't feel safe moving on this court a lot of the time. The bounce is not consistent at all and we weren't able to practice on this court until yesterday for the first time. It's just not acceptable to me with so much on the line and so much at stake.
“As I said in my press conference tonight, as a player I really feel disrespected by the WTA. I think most of us do.”
American Jessica Pegula defeated Kazakhstan's Elena Rybakina 7-5, 6-2 in 83 minutes in the other singles group stage match at the $9 million outdoor hardcourt showdown.
The big-serving Rybakina looked poised to capture the first set when she stepped to the service line leading 5-3 in the opener but Pegula raised her return game for a crucial break.
Pegula used that momentum to close out the set by winning four straight games and her clean ball striking overwhelmed the Kazakhstani, who tallied 35 unforced errors in the match.
“I feel like she just made a couple careless errors and I was able to take advantage of it at the right time and ride that momentum all the way through the second set,” said Pegula, who won 10 of the last 12 games.
“I thought I was returning really well, reading her serve a little bit more, and was able to play some good tennis.”
Two groups of four players will compete in round-robin matches through to Friday with the two top finishers in each group advancing to Saturday's semi-finals. The final is next Sunday.
Sabalenka is trying to hold off second-ranked Iga Swiatek, the reigning French Open champion from Poland, to claim the year-end crown taken last year by four-time Grand Slam winner Swiatek.
Sabalenka can clinch the year-end top spot by going 2-1 in the group stage and reaching the final no matter what Swiatek does.
Swiatek must win the title in North America to have a chance of regaining the top spot she lost after 75 weeks due to Sabalenka's run to the US Open final in September.
“It's good to reach one of your goals but you still need to work hard and bring your best tennis,” said Sabalenka, who also reached the semi-finals at Wimbledon and the French Open. “When you reach No 1 I feel like you have this huge target on your back.”
Monday's opening matches in the other group send Swiatek against reigning Wimbledon champion Marketa Vondrousova of the Czech Republic and 19-year-old American Coco Gauff, the US Open champion, against Tunisia's Ons Jabeur.