CANCUN, Mexico — The matchup between Iga Swiatek and Coco Gauff is shaping up to be a defining rivalry on the Hologic WTA Tour for years to come.
As they prepare to face off for the 10th time at the GNP Seguros WTA Finals, Swiatek holds the advantage with eight wins out of nine previous encounters.
“She’s definitely one of the best players ever and in our generation, too,” Gauff said. “I mean, it’s something that I have to do better against her.”
WTA Finals: Scores | Draws | Order of play
Swiatek had dominated their head-to-head, winning seven matches in a row. However, in August, Gauff claimed a three-set victory over Swiatek in the Cincinnati semifinals, showing signs of improvement. Gauff went on to win her first major at the US Open, but Swiatek got her revenge with a 6-2, 6-3 win in Beijing, although Gauff was struggling with a shoulder injury.
Previously, Swiatek and Gauff usually faced each other in the early rounds. Now, as the No. 2 and No. 3 ranked players, they often meet in the semifinals or finals.
“The more I can play against her, the more I can get better,” Gauff said. “Hopefully, this time I would love to get a win in the head-to-head. We could potentially play each other many more times if we both continue to do well.
“At this rate, we probably will have the most matches ever at the end of our careers.”
The second round-robin singles matches in the Chetumal Group begin at 5 p.m. local time.
 Iga Swiatek vs.  Coco Gauff, 5 p.m. local time
The case for Swiatek: Swiatek’s dominance in their previous matches, winning all eight in straight sets, gives her confidence heading into this match.
She is coming off a comeback win against Marketa Vondrousova in the first round-robin match, where she overcame a 5-2 deficit to win 10 of the last 11 games, including the tiebreak.
A victory here would put Swiatek in a strong position to advance to the semifinals and mark her 10th win over a Top 10 player this year. The last player to achieve this in consecutive seasons was Serena Williams in 2013-14.
Despite Gauff enjoying some support from the crowd, Swiatek seems to have the largest following here.
“I even felt that two years ago in Guadalajara,” Swiatek said. “The support that we have here is really amazing. I’m happy that so many Polish people came because I see them more and more every year in any place I go. It’s something that other players don’t have that much, so I’m really happy that I have this support.”
The case for Gauff: Gauff needs to see the head-to-head record from a positive perspective, considering she and Swiatek have split their past two matches.
Gauff also gained momentum with a convincing 6-0, 6-1 win over Ons Jabeur, ending her 0-7 streak at the WTA Finals.
After the match, Gauff revealed a change in her coaching team, with Pere Riba no longer on board. Riba and Brad Gilbert were credited with helping Gauff achieve her best results to date, including titles in Washington, D.C., Cincinnati, and the US Open. Gilbert is now working with Gauff in Mexico.
Fun fact: Gauff is aiming to become the first teenager since Ana Ivanovic in 2007 to win multiple matches at the WTA Finals.
 Ons Jabeur vs.  Marketa Vondrousova, to follow
The case for Jabeur: This is a great opportunity for Jabeur to reverse her Wimbledon final loss to Vondrousova, where she fell 6-4, 6-4.
Jabeur initially expected to face Swiatek after her loss to Gauff, but now prepares for Vondrousova.
“It’s going to be a very tough match,” Jabeur said. “I mean, difficult conditions for both of us. I think she plays really well and she’s someone who doesn’t give up any free points. She’s a lefty and on this type of court, I feel it suits her very well.”
In a challenging season, Jabeur found success in China, winning seven out of nine matches and clinching the title in Ningbo.
The case for Vondrousova: Vondrousova has turned their head-to-head around, winning their last three matches, including a victory at this year’s Wimbledon.
Vondrousova’s game of consistency and wide margins helped her take a 5-2 lead against Swiatek in the previous match. She will need to replicate that strong start against Jabeur, who also has a diverse game with drop shots in her arsenal.
Both players lost their opening matches, making this a crucial match. The loser will fall to 0-2 and face an uphill battle to qualify.
Doubles action: Wednesday features three doubles matches due to the rescheduling caused by Monday’s cancellation. No.5 seeds Demi Schuurs and Desirae Krawczyk face off against No.8 seeds Nicole Melichar-Martinez and Ellen Perez. In another match, No.7 seeds Gabriela Dabrowski and Erin Routliffe take on No.6 seeds Vera Zvonareva and Laura Siegemund. The late-night action features No.1 seeds Coco Gauff and Jessica Pegula against No.4 seeds Barbora Krejcikova and Katerina Siniakova. Both teams are currently 0-1.
Jessica Roberts serves up the latest in the world of tennis. With a love for the racket sport, she reports on tennis matches, player rankings, and Grand Slam events, ensuring readers stay informed about the tennis world.