As Elena Rybakina trailed Zheng Qinwen by a set and a break in their tight group-stage tussle at the WTA Finals in Riyadh on Monday, the odds were not in her favour. Still, she fought hard, retrieved the break and as her confidence grew, her own serve, one of the most destructive weapons in the sport, fell into place. Rybakina rolled through four successive games to force a final set.

That sequence of play from Rybakina was a reminder of the high level she has produced to establish herself as one of the leading players on the WTA tour, but this time it was fleeting. She was visibly fatigued in the final set as Zheng regained control and secured her first win at the WTA Finals, closing out the match 7-6 (4), 3-6, 6-1.

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Rybakina’s battles with fatigue and her 0-2 record in Riyadh underline her struggles at the end of a difficult season. Things had been going so well at the beginning of the year as she positioned herself alongside Iga Swiatek and Aryna Sabalenka as one of the leading players of this generation. She seemed to be moving towards taking the next step in her career by winning her second grand slam title after her maiden triumph at Wimbledon in 2022.

By the semi-finals of the Madrid Open in May, Rybakina had compiled a 30-4 record in 2024 with three titles, including a spectacular win against Swiatek on clay en route to her Stuttgart Open title. Even in defeat in Spain, a brutal three-set loss against Sabalenka in one of the matches of the year, her performance only further emphasised the excitement surrounding her.

Those high hopes, however, dissolved quickly in the second half of the season for a variety of reasons. Rybakina has struggled to remain healthy since last year and in 2024 alone she has withdrawn or retired from 10 events with a variety of illnesses and injuries. Although Rybakina has been reluctant to discuss in depth her health, even chastising reporters for asking the “same” questions on the subject during the French Open, she has cited insomnia as one of her problems this year.

Even when things were going well, Rybakina’s partnership with her former coach Stefano Vukov generated attention. Vukov, a relatively young Croatian coach, was Rybakina’s first formal, individual coach from when she committed fully to tennis at the end of her teenage years. They enjoyed great success together, building her ranking and then winning her first grand slam title at Wimbledon in 2022.

But Vukov’s intense approach did not endear him to onlookers. During matches, his extremely critical and negative presence was an uncomfortable sight, particularly alongside her understated demeanour. In their practice sessions, he would hassle her with instructions after almost every point. Their coaching dynamic attracted public criticism from a number of prominent former players, including Pam Shriver, along with some support.

After withdrawing from the US Open with an injury, Rybakina finally opted to split with Vukov and, in the leadup to her matches in Riyadh, Rybakina revealed some of the most surprising coaching news in recent years: from next season she will be working with the former Wimbledon champion Goran Ivanisevic, who coached Novak Djokovic to 10 grand slam titles between 2019 and 2024.

After being out of action for more than two months, the WTA Finals came too soon for Rybakina and she is now out of contention for the semi-finals. Next year, one of the most significant questions on the tour will be whether Rybakina can rebuild her form, improve her health and re-establish herself among the elite.

As Rybakina was handed her second defeat, the top seed, Sabalenka, continued her imperious form by beating Jasmine Paolini, the fourth seed, 6-3, 7-5 to move to 2-0 in the tournament and win the Purple Group.

Sabalenka, who saved two set points in the second set after a spirited fight from Paolini, will confirm her status as the year-end No 1 if she defeats the fifth seed Rybakina in an otherwise dead rubber on Wednesday. The winner between Zheng, the seventh seed, and Paolini, meanwhile, will join Sabalenka in the semi-finals.

While the opening day in Riyadh attracted a solid audience, the crowds have been sparse on days two and three. Once again, the best women’s tennis players are competing in one of the biggest events in the world in front of a very small number of people.