Elena Rybakina’s withdrawal on the eve of the WTA Finals in Indian Wells left Group 1 without its favourite and guaranteed a new champion. On Sunday, fourth seed Coco Gauff and fifth seed Jessica Pegula of the United States meet three ranking points apart.

Eighth seed Linda Noskova of the Czech Republic faces Marta Kostyuk of Ukraine, the first alternate she beat twice this summer.

The defending champion and world No. 1 had won more titles (four), matches (54) and top-10 matches (10) than any other player this season, and had never lost to Noskova. “My body is just not physically ready to compete,” the Kazakh said in a statement released by the WTA on Saturday.

Nobody has defended the WTA Finals title since Serena Williams in 2014, and that will not change this year. Gauff, champion in 2024, is the only former winner left in the group. Elina Svitolina, champion in 2018, plays in Group 2.

Noskova vs Kostyuk, a Wimbledon rematch

Kostyuk, 24, ranked No. 10, played the best season of her career. She won her first WTA 1000 title in Madrid, beating Mirra Andreeva in the final, and added a title in Rouen. She also reached her first two Grand Slam semi-finals, at Roland-Garros and Wimbledon.

Most of that came on clay, where she went 16-1 this year. On hard courts, her record stands at 14-10.

Noskova leads their head-to-head 2-1 and won both of their meetings this summer. She beat Kostyuk in the Wimbledon semi-finals on her way to the title. She beat her again in the last 16 of the US Open.

Noskova, 21, is one of three debutants at the event, with Andreeva and Karolina Muchova. She won back-to-back grass titles in Berlin and at Wimbledon, beating Pegula and Muchova in the finals. She entered the top 10 in June and rose to a career-high No. 6 in August.

Only Rybakina hit more aces this season, 438 to Noskova’s 347. The Czech has not played since losing to Ekaterina Alexandrova in the last 16 in Beijing in September.

“It’s the most competitive tournament that one can play in a year,” Noskova said at media day. “Also the situation where you can lose a match and win the whole thing is very, very new to me.”

Twelve players have lost a round-robin match and gone on to win the title. Gauff was the most recent, in 2024.

Gauff vs Pegula for No. 4

Gauff and Pegula are separated by three points in the race for year-end No. 4, with 5,763 for Gauff and 5,760 for Pegula. Each round-robin win is worth 200 points.

Their head-to-head stands at 5-5. They meet at the WTA Finals for a fourth consecutive year, with Pegula leading 2-1 at the event. Only Agnieszka Radwanska and Petra Kvitova (2011-2015), and Martina Navratilova and Pam Shriver (1983-1986), had faced each other at four or more editions in a row.

Gauff won both of their meetings in 2026, in the Wimbledon quarter-finals and in the Cincinnati final, her only title of the season. She won 27 matches at WTA 1000 level this year, more than any other player, and is 10-0 against Americans. At 22, she is the youngest player to qualify for five consecutive WTA Finals since Martina Hingis.

Pegula, 32, is the oldest player at the event since Venus Williams in 2017. Her 50 wins this season put her level with Andreeva, behind only Rybakina, and she won titles in Charleston and Dubai. She has played one match since the US Open, a loss to Jelena Ostapenko in her opening match in Wuhan.

“I feel the level is just so high right now, and there’s so much depth,” Pegula said at media day.

Her week started under scrutiny. A livestreamed practice session picked up her private comments about Andreeva, whom she called a “diva” who “needs to be humbled”, and the WTA apologised and switched off the sound on its practice courts.

The top two in each group reach the semi-finals, where each group winner meets the runner-up of the other group. An unbeaten champion would earn $3.37 million and 1,500 ranking points.