NEW YORK, NY, USA - No.4 seed Elise Mertens and Aryna Sabalenka kept their hopes of a first major title together alive with a 6-3, 7-5 win over Viktorija Golubic and Sara Sorribes Tormo at the US Open.

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Mertens and Sabalenka were back-to-back winners at the BNP Paribas Open and Miami Open to become the first team since Martina Hingis and Sania Mirza (2015) to win the Sunshine Double.

"When both of our serves are working, we can come to the net and volley. I think we can be very dominant in that way, so we just tried not to miss too many returns..." Mertens explained as Sabalenka laughed.

"Just put the ball in and see how it goes," Mertens continued. "We feel comfortable with each other. We started playing this year, and of course, there's some adjustments we've made, and I think it's working. Outside the Grand Slams, the Sunshine Double are two of the biggest tournaments in tennis, so we want to keep doing our best at the big tournaments."

Mertens and Sabalenka navigated through two tough sets to advance after 81 minutes on Court 17.

"I think we just tried to stay up with our energy, and that helped us a lot to be in the game," Sabalenka said. Other times, our energy can go up and down, so we were just trying to be aggressive with the game and also with our emotions, screaming 'Come on!' These things really help us. I think our net game is much better right now and that helps us on important points.

"We just try to focus on ourselves, what we can do, and what we can do better," Mertens added. "We don't really look at the draw, so we don't know the opponents until the day or two days before, so we just work on what we can improve."

Mertens, who sported a t-shirt dedicated to the TV Show Friends to her post-match press conference, and Sabalenka have reached the quarterfinals or better in three of this year's four major tournaments - including Roland Garros, where they made the semifinals - and will next play either No.12 seeds and French Open finalists Duan Ying-Ying and Zheng Saisai or Anastasia Pavlyuchenkova and Anastasija Sevastova, who upset No.7 seeds Latisha Chan and Chan Hao-Ching earlier in the day.

"It's only getting tougher from here on out," Mertens said. "If the seeds don't fall, it's going to be tough to beat them. We'll focus, match by match, and we'll see how it goes."

No.3 seeds and 2017 Miami Open champion Gabriela Dabrowski and Xu Yi-Fan survived a second set hiccup to dispatch the German duo of Anna-Lena Friedsam and 2014 US Open mixed doubles champion Laura Siegemund, 6-3, 0-6, 6-2.

Dabrowski and Xu next, who finished runner-up at this year's Wimbledon Championships, next face another unseeded team in Viktoria Kuzmova and Aliaksandra Sasnovich, who narrowly dispatched Danielle Collins and Ellen Perez, 7-6(4), 5-7, 7-5, for a spot in the semifinals.