NEW YORK, Sept 10 (Reuters) - Elena Rybakina overpowered Coco Gauff 3-6 6-4 6-4 in a fierce U.S. Open semi-final on Thursday to secure a title showdown with defending champion Aryna Sabalenka and stay on course for a third Grand Slam crown.
Sabalenka eliminated top-ranked American Jessica Pegula 7-5 6-2 to move one victory away from a third straight title at the year's final Grand Slam, a feat last achieved by Serena Williams in New York from 2012 to 2014.
Rybakina already knows she will leave Flushing Meadows as the new world number one and can deliver another body blow to the Belarusian by denying her a fifth major title.
"She's an unbelievable player, she played really well today, so I definitely need to step up my game," said Rybakina, who beat Sabalenka in the Australian Open final in January.
"I must serve better than I did today and stay aggressive."
Gauff absorbed relentless pressure and stayed strong from the back to draw errors from the Kazakh, breaking in the sixth game and taking the first set in front of a roaring crowd that included former first lady Michelle Obama.
"I felt in the first set that it was a very good start and it was one break, but of course, there are nerves," a relieved Rybakina said after reaching her maiden U.S. Open final.
"Coco's a great player, it's always tough to play against her ... it's very difficult to dictate the rallies. I just took a deep breath and just had a positive talk with myself to try and show some good tennis."
RYBAKINA COOL UNDER PRESSURE
Rybakina capitalised on some sloppy play by the fourth-seeded American in the second set to level the match at one set apiece and silence the Arthur Ashe Stadium crowd, before ramping up the intensity in the decider.
The 27-year-old gained control with her power and broke to go 5-3 ahead in the decider, before Gauff hit back with a break of her own, but the American's comeback bid faltered when she could not hold serve and Rybakina broke to close out the win.
Gauff's defeat, coupled with that of compatriot Jessica Pegula in the earlier semi-final, means that no American woman will have played in a Grand Slam final this year, marking the first time this has happened since 2006.
"I know you guys wanted Coco to win, but it was a real battle," Rybakina told the crowd.
"A few moments went my way and in the end, I tried to stay focused and aggressive and win the match."
SABALENKA FINDS HER GROOVE
Earlier on Thursday, Sabalenka took her time to find top gear but once she hit her stride there was no stopping her.
Third seed Pegula had no answer to the Belarusian's power and allowed mistakes to creep into her game in the second set.
"I was so desperate for the win, I wanted it badly," said Sabalenka, who will play in the final for a fourth straight year.
Sabalenka is bidding to join Williams and Chris Evert as the only women to win three straight U.S. Opens in the Open Era, which began in 1968.
"You guys are the best, your respect for me is priceless," Sabalenka told a the crowd after beating Pegula.
"I know you wanted her to win but thank you for being so respectful to me."
Home fans will have an all-American men's semi-final to savour on Friday when Ben Shelton and Frances Tiafoe meet for a place in the title clash, after top seed Alexander Zverev takes on Russian Karen Khachanov.
(Reporting by Shrivathsa Sridhar, Amy Tennery and Janina Nuno Rios in New York; Editing by Peter Rutherford)
