British 18-year-old Emma Raducanu has become the first qualifier to ever reach a Grand Slam final by defeating Greek 17th seed Maria Sakkari 6-1, 6-4 at the US Open.

On Thursday, Raducanu, ranked 150th, became the youngest Grand Slam finalist since 17-year-old Maria Sharapova won at Wimbledon in 2004.

She advanced to Saturday's US Open final at Arthur Ashe Stadium against 19-year-old Canadian Leylah Fernandez.

It's the first Slam final between teens since 17-year-old Serena Williams beat 18-year-old Martina Hingis at the 1999 US Open, and just the eighth all-teen Slam final in the Open era (since 1968).

Fernandez beats world number 2 Sabalenka

Canadian teen sensation Leylah Fernandez advanced to her first Grand Slam final on Thursday by defeating world number two Aryna Sabalenka of Belarus in the US Open semi-finals.

The 19-year-old prodigy eliminated Wimbledon semi-finalist Sabalenka 7-6 (7/3), 4-6, 6-4 and could capture her first Slam crown on Saturday at Arthur Ashe Stadium.

"I don't know how I got that last point in but I'm glad it was and I'm glad I'm in the finals," Fernandez said.

Fernandez, a 73rd-ranked left-hander, made Sabalenka her third top-five victim of the Open, having earlier ousted defending champion Naomi Osaka and fifth-seeded Elina Svitolina.

READ MORE:Osaka mulls break from tennis after US Open loss to Canada's Fernandez

First Slam final between teens since 1999

Not since Serena Williams in 2012 at Wimbledon had a player beaten three rivals ranked in the top five at a Grand Slam.

When Fernandez meets 150th-ranked Raducanu in the final, it will be the first Slam final between teens since 17-year-old Williams beat 18-year-old Martina Hingis at the 1999 US Open –– and only the eighth all-teen Slam final in the Open era (since 1968).

"I don't care. I just want to play a final," Fernandez said. "I'm going to enjoy my victory and worry about it tomorrow," Fernandez said.

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