Stephens, who missed 11 months with a left foot injury before returning in July, defeated Williams 6-1, 0-6, 7-5.
New York: Seven-time Grand Slam champion Venus Williams was knocked out of the US Open after facing a three-set defeat against Sloane Stephens in a thrilling semifinal on Thursday evening.
Stephens, who missed 11 months with a left foot injury before returning in July, defeated Williams 6-1, 0-6, 7-5 at the Flushing Meadows to dance into her first-ever Grand Slam final.
The match featured wild momentum shifts which lasted entire sets, as evidenced by the scoreline.
"I have no words to describe what I'm feeling, what it took to get there," said the American after her victory. "It's just a journey. I have no words. When I started my comeback, if someone told me I'd make two Grand Slam semis and a final, I would probably have passed out."
"It required a lot of fight and a lot of grit. I just worked my tail off and ran down every ball," she added.
24-year-old Stephens is the 14th unseeded player to advance to a Grand Slam final in the Open era, and only the fourth at the US Open after Venus Williams (1997), Kim Clijsters (2009) and Roberta Vinci (2015). Only one of those, Clijsters, has captured the title.
Stephens will now face 13th-seeded Madison Keys---who came out with a dominant performance and defeated fellow American CoCo Vandeweghe in straight sets, 6-1, 6-2---in the summit showdown on Saturday.
It will be the first all-American final at the US Open since 2002, when Serena Williams defeated Venus, and the first all-American Grand Slam final not involving a Williams since 1990, when Martina Navratilova defeated Zina Garrison at Wimbledon.
The two players would meeting for the third time overall, all of which have come this summer; Keys was victorious in the final at the Bank of the West Classic in Stanford in straight sets, and prevailed in three at another US Open Series event in Cincinnati in August.