RIYADH, Saudi Arabia — Jelena Ostapenko is trying dutifully to explain the dynamics of her doubles partnership with Hsieh Su-Wei.
“Chemistry,” Ostapenko intones. “The balance …”
The irrepressible Hsieh cannot help but interrupt.
“We both are cuckoo!” she says, practically shrieking.
Ostapenko shakes her head and rolls her eyes.
“We both understand each other,” Ostapenko says. “Just looking at each other, we know what to do.”
And then they look at each other — and dissolve into laughter.
This is the kind of crackling energy — synergy, really — that helps win matches. Deep experience is the other thing that defines the four teams to reach the semifinals here at the WTA Finals.
Ostapenko is only 28 years old, but she turned professional 14 years ago, winning a Roland Garros singles title along the way. Hsieh, at 39 the oldest player to qualify, is the ultimate mercenary with 35 career titles — with nine different partners (none of them, notably, Ostapenko). You’ll find her picture in Webster’s Dictionary under the word “crafty.”
Seven of the 16 doubles players gathered here are 30-plus. Four are 29 and three more 28. It works out to an average age of 30 on the button, three-and-a-half years older than the average singles player.
“I am upping that number,” Hsieh said, smiling.
The four teams to advance to the semifinals are fairly dripping with experience: No. 1 Katerina Siniakova-Taylor Townsend, No. 4 Elise Mertens-Veronika Kudermetova, No. 6 Ostapenko-Hsieh and No. 7 Timea Babos-Luisa Stefani.
Consider the fate of Mirra Andreeva, 18, and partner Diana Shnaider, 21. They were the youngest team to qualify for the WTA Finals, in terms of combined age, since a 20-year-old Martina Hingis and 19-year-old Anna Kournikova in 2000.
Ranked No. 9 and No. 21 in singles, respectively, they were eliminated on Tuesday.
Nothing better
The chase began before the 2024 season.
“My coach was very aggressive to catch Alona,” Hsieh explained. “It did not happen the first time, but it happened. She’s very popular girl. Hot, hot, hot.”
Ostapenko played last year with Lyudmyla Kichenok, but opted for Hsieh in 2025. She was asked to give a scouting report
“Su-Wei is very up and down — no, no, I’m joking,” Ostapenko said. “I think that she has really good hands. She’s one of the best volley players in the world.”
Hsieh on Ostapenko: “She hit the ball good. Very aggressive. And she tries really hard. This is the most important stuff, because you don’t always play your best.”
This is the sixth WTA Finals for the diminutive Chinese player. A dozen years ago, she won in her very first appearance, with Peng Shuai. In 2019, she lost in the final with Barbora Strycova and again in the 2021 final with Mertens. She and Mertens were in the field a year ago in Riyadh’s debut.
Hsieh has actually retired once already.
“I was not doing any sport for one and one-half years,” she said. “It was an accidental comeback. I couldn’t find something better to do in the retired life.”
Oddly enough, Ostapenko (37-15) and Hsieh (33-17) qualified but failed to win a title together this year.
Hsieh said that her experience helps compensate for any deterioration in her physical skills. Optimism might be her biggest asset.
“The good thing will come, just need to be patient. When the time comes, I will take it.
What goes around, comes around
Three years ago, Mertens and Kudermetova went all the way, winning the title at the year-end championship in Fort Worth. They parted ways afterward.
Mertens played with Storm Hunter in 2023 and Hsieh in 2024. Kudermetova, after playing with a number of partners in 2023, was more exclusive with Chan Hao-Ching last year.
When Mertens was looking for a new partner for 2025, she texted Kudermetova.
“Hey, are you up for teaming up again?” she asked.
Kudermetova did not immediately respond.
“No,” she said, laughing, “I waited a few hours — to make her nervous.”
Said Mertens, “She said yes, so here we are again.”
Their chemistry meshes nicely.
“We’re both kind of introverts,” Mertens said. “So we like quiet time and also because we’re singles players. We practice together and we’re going to be better players, of course.”
Indeed, the two are anything but doubles specialists. Mertens is currently ranked No. 20 in singles, while Kudermetova is 30. Mertens won two singles titles this year, in ‘sHertogenbosch and Singapore.
“Sometimes you are not good enough in singles and doubles helps you for sure,” Kudermetova said. “If you lose early in singles, you’re still in the tournament. You still practice, play matches. That’s why the dial pushes up for singles.
Added Mertens, “And if you win a couple of matches, it gives you confidence. You practice serve, volleys, reaction … it’s only a plus to play doubles.”
The two combined for this year’s Wimbledon title.
This is Mertens’ seventh appearance at the WTA Finals — and Kudermetova, playing with her for the second time, is her fifth partner. Here’s the breakdown: 2018 (Demi Schuurs), 2019 (Aryna Sabalenka), 2021 (Hsieh Su-Wei), 2022 (Kudermetova), 2023 (Storm Hunter), 2024 (Hsieh), 2025 (Kudermetova).
Wait — what? Sabalenka — currently the World No.1 in singles — qualified for the year-end championship in doubles before singles?
“Yes,” Mertens said. “Still very young, had a lot of power. I remember sometimes the ball would go beside my ear [on the serve] … scary. She was a great player already. We had a lot of success. During COVID-19 we practiced a lot in Australia.
“She had so much potential. I knew. She just needed some consistency at that stage of her career. She managed mentally to stay stable and now she’s at the top of the game.”
Playing again with Mertens has freed Kudermetova to be even more honest than before.
“Sometimes during the match, I can say this part of my game I don’t think is working so well — let’s see what we can do better,” Kudermetova said. “In an early match at Wimbledon, she said, `I don’t feel my return or the forehand. I cannot play with the angle.’
“I said, `OK, let’s do something else.’ ”
Mertens smiled and said, “And we won it.”
Getting better … all the time
If it seems like these elite doubles players do a fair amount of jumping around, that’s because they do. It’s a finite universe and, over the long haul of a season, traveling the world in such close quarters, it can get a little claustrophobic.
Given different family dynamics, travel schedules don’t always mesh.
And then there’s the singles factor. The No. 3 team of Dabrowski and Routliffe, as well as No. 7 Timea Babos and Luis Stefani are not ranked in singles at all. Still, a number of players are ranked relatively high in singles and that takes precedent over doubles scheduling, as in the case of Andreeva and Shnaider.
Babos and Stefani win to remain in the hunt at the WTA Finals
Ostapenko was a winner this year in Abu Dhabi with Ellen Perez and Charleston with Routliffe. When Townsend said she wasn’t ready for the WTA 1000s in Beijing and Wuhan, Siniakova promptly won Wuhan with Storm Hunter and Seoul with her old partner Barbora Krejcikova. Townsend, meanwhile, won the Osaka crown with Kristina Mladenovic and reached the Tokyo semifinals with Ellen Perez.
Thirteen years ago, Babos won the title in Birmingham with the 26-year-old Hsieh. She’s gone on to collect seven Grand Slam doubles titles, four of them at Wimbledon. Does Babos, 32, imagine herself playing until she’s 39?
“Me, no,” Babos said. “I say that now. I keep my word, I’m not playing at the age of 39. Hsieh’s lifestyle is unique, her body, her game.”
Several weeks ago, when Siniakova was looking for a partner in Ningbo, she linked up with Hsieh. They won two matches and reached the semifinals.
Siniakova, 29, just won the Martina Navratilova trophy for year-end doubles No. 1 for the fifth time. Thirty-nine, she said, seems like a stretch.
“Everybody is saying I can play doubles for another 20 years, but I would love to have a family, so we’ll see how it goes,” Siniakova said.
“But Su-Wei is amazing. I remember when I was just starting, she was already so good — and she’s still playing. Not everyone is playing — no, no one is playing like her.”
Hsieh isn’t sure when she’ll retire again.
“If I’m healthy and enjoy, I’ll keep doing,” she said. “I’m getting better and better.”