NEW YORK, NY, USA -- The exceptional season on American hardcourts keeps on rolling for Elise Mertens and Aryna Sabalenka, as the No.4 seeds overcame the all-American tandem of Caroline Dolehide and Vania King, 4-6, 6-3, 6-4, to book a spot in the US Open women's doubles final.

It will be the first-ever Grand Slam final for both Mertens of Belgium and Sabalenka of Belarus, after fighting back from a set down to squeak past the first-time pairing of Dolehide and 2010 US Open women's doubles champion King. The match concluded after two hours and 19 minutes of tense all-court play under the closed roof of Louis Armstrong Stadium on Friday afternoon.

"It was really close, the whole match," Mertens told the press, after their win. "I think we made the difference by just believing in ourselves, playing aggressive, and staying positive."

Sabalenka agreed, saying that "as long as we stay in the match, as long as we focus on our game, focus on being aggressive, then I think we have a lot of chances to win matches."

The fourth seeds pulled off the "Sunshine Double" earlier in the season by going 10-0 en route to back-to-back titles at Indian Wells and Miami, and are still notching their best results at the most prestigious events in the United States.

The victorious team won 72 percent of points on their first serves combined, converted four of their ten break points, and fended off 16 of the 19 break points the Americans held in the clash.

"We’ve been close a couple times, quarters at Wimbledon, semis at the French, so it’s a really nice feeling that we’re accomplishing good things," said Mertens, reflecting on their solid play in Grand Slam events this season. "We’re really happy that we’re in the finals, but it’s not done yet, so we’re going to go for it on Sunday."

Mertens and Sabalenka will face another top team in the final: No.8 seeds Victoria Azarenka of Belarus and Ashleigh Barty of Australia. Barty is the defending champion, having won the title last year with CoCo Vandeweghe, and she and Azarenka are on a roll, having dispatched Viktoria Kuzmova and Aliaksandra Sasnovich with a loss of just a single game in their semifinal on Thursday.

However, Mertens and Sabalenka go into the final knowing that they defeated Azarenka and Barty in the only prior meeting between the two teams, in the semifinals of Miami as part of their 10-match winning streak during March's "Sunshine Double."

"We played them once," said Mertens. "We’re going to look at how they play. They won pretty easily their last couple of matches, so we’ll try to break their rhythm."

The American team broke serve in the first game of the match, as King and Dolehide both found overhead winners in the last two points. The fearsome Sabalenka forehand made a stirring appearance to convert a break point and reach parity at 3-3, but Dolehide’s powerful game put her squad up another break at 5-4. Dolehide, who turned 21 on Thursday, followed up with a service hold to clinch the one-set lead.

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The seeded team rebounded in the second set, with Mertens crushing an overhead to force an error from Dolehide and earn a service break for 3-1. That lead held up through 5-3, where Mertens faced a 0-40 deficit on her serve before strong net play pulled her team to deuce. Two points later, a Sabalenka putaway leveled the match at one set apiece.

Mertens and Sabalenka got out to an early lead in the final set, as a volley by the Belgian forced a netted error from Dolehide on the No.4 seeds’ third break point of the game to go up 2-1. Aggressive play by Dolehide and pinpoint shots down the line by King gave the Americans two break points at 4-3, but Sabalenka punched punishing volleys on those chances en route to a hold for 5-3.

With Sabalenka serving for the match at 5-4, the American team held two more break points to level the set, but the Belarusian saved those with a powerful forehand and a huge serve respectively. Dolehide and King fended off one match point, but Sabalenka scampered all over the court, eventually powering through her opponents, to queue up a second match point, which she converted with a final forehand winner.