Daria Kasatkina was overpowered by Iga Swiatek in their opening match of the WTA Finals in Fort Worth, as the world number one earned a comfortable straight-sets victory on Tuesday.
Tournament favorite Swiatek prevailed 6-2 6-3 against number eight seed Kasatkina at the hard-court showpiece, meaning the Pole has won each of her last five meetings with her Russian rival.
Swiatek broke Kasatkina at the first opportunity in each set and was largely untroubled in Texas, converting three of the seven break points she earned while saving all three she faced from her opponent.
The Pole, 21, is hotly fancied to add to her eight titles this season and is the only Grand Slam winner among the eight contenders for the WTA Finals singles crown, where a total of $5 million in prize money is up for grabs.
Kasatkina, 25, is making a maiden appearance in the season-ending WTA event, having won two tour titles this year.
The Russian women’s number one will hope to get on the scoreboard when she plays America’s Coco Gauff on Thursday, in what will be the second of three round-robin matches in the group stage.
Kasatkina, Swiatak, Gauff and France’s Caroline Garcia have all been drawn in the ‘Tracy Austin Group’.
In Tuesday’s other match, Garcia overcame Gauff in straight sets to get her campaign off to a winning start.
The ‘Nancy Richter Group’ continues on Wednesday when Ons Jabeur of Tunisia takes on American Jessica Pegula, while Aryna Sabalenka of Belarus plays Greek rival Maria Sakkari.
In the opening round of matches on Monday, Sabalenka beat Jabeur while Sakkari overcame Pegula.
The top two players from each group will progress to the semifinal stage of the tournament.
Despite the defeat for Kasatkina, there was Russian success elsewhere in Texas on Tuesday as Veronika Kudermetova won her opening match alongside Belgium’s Elise Mertens in the WTA Finals doubles event.
The pair battled back to beat Ukraine’s Liudmila Kichenok and Latvia’s Jelena Ostapenko in a 3-6 6-1 10-6 victory in the ‘Pam Shriver Group’.
Seeded fourth, Kudermetova and Mertens next face Brazilian-Kazakh duo Beatriz Haddad Maia and Anna Danilina in their second group-stage match on Thursday.