NEW YORK, NY, USA - 2010 champion Vania King and partner Carole Dolehide continued their fairytale run into the US Open semifinals, upsetting No.14 seeds Lyudmyla Kichenok and Jelena Ostapenko, 7-6(2), 6-4.

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King and Dolehide are playing together for the first time but have only dropped one set through four matches, edging past the Ukrainian/Latvian team after one hour and 47 minutes.

"I think we were just talking about playing together a little bit since the last US Open and the last year," Dolehide recalled after the match. "Vania reached out, and it wasn’t that hard to say yes, so we decided to do it."

"We didn’t even know if we would get in," King added. "All of it has been pretty lucky and serendipitous."

A former World No.3 in doubles King won back-to-back major tournaments in women's doubles with Yaroslava Shvedova at the 2010 Wimbledon Championships and US Open, finishing runner-up at the latter the following year, but hadn't been past the quarterfinals of any major tournament since, struggling with various physical issues - most recently an ankle injury - that kept her off court for much of 2019.

"It means so much," King said. "The last few years have been tough because I’ve been dealing with a lot of injuries, and kind of the same injury for the past few years. Caroline is such a great girl, and a great player, so I’m really excited to be doing this with her.

"Maybe it’s my age showing," the 30-year-old added, "but I’m definitely calmer, honestly, than I was in early years. I’m much more appreciative of the time I have on court. Whether I win or lose, I take things day by day, and I really appreciate everything I have. I’m really happy to just be here."

Playing just her third tournament since January, King and Dolehide struck a total of 24 winners to just 14 winners and broke serve four times to defeat Kichenok and Ostapenko, who stunned reigning Wimbledon winners and No.2 seeds Hsieh Su-Wei and Barbora Strycova in the previous round.

"We actually had a practice match against a few of our friends, and I felt it right then," Dolehide said of their on-court chemistry. "I was thinking about how quick Vania is at the net with my big serve. We’re figuring out how to work with our gamestyles, but I felt good right away."

King felt the true turning point came in the first round, when they fell behind a set to countrywomen Desirae Krawczyk and Jessica Pegula before rallying to win the match in three.

"We calmed down. Playing a match is always a little bit different. Since then, we’ve been doing better and better."

Standing between the all-American duo is No.4 seeds Elise Mertens and Aryna Sabalenka, who reached their second major semifinal as a team on Tuesday with a win over Roland Garros runner-ups and No.12 seeds Duan Ying-Ying and Zheng Saisai.

"They’re a great team. I watched a little bit of them yesterday, not knowing that they would be our opponents. I enjoy watching doubles and tennis, in general, so I’m really excited because that’s what we want. We want to play good teams to test ourselves and see if we can match them or be better."

Earlier in the day, Viktoria Kuzmova and Aliaksandra caused a big upset by knocking out No.3 seeds and Wimbledon finalists Gabriela Dabrowski and Xu Yi-Fan, 2-6, 6-3, 6-3. They'll face No.8 seeds and Internazionali BNL d'Italia champions Ashleigh Barty and Victoria Azarenka in the first doubles semifinal on Thursday.