New York: Canadian teenager Bianca Andreescu reached the final in her U.S. Open debut by beating No. 13 seed Belinda Bencic of Switzerland 7-6 (3), 7-5.
The 15th-seeded Andreescu trailed Bencic 4-1 and 5-2 in the second set before taking the last five games.
"If someone told me a year ago that I would be in the finals of the US Open this year, I would tell them 'You are crazy,'" official website of US Open quoted Andreescu as saying.
Andreescu, 19, is only the second women's Grand Slam finalist from Canada. Eugenie Bouchard is the first woman from Canada to make it to the finals of a Grand Slam.
This win is Andreescu's 13th consecutive victory and she is only the third player to reach the final in her US Open main draw debut.
Andreescu had earlier faced Serena Williams in the Rogers Cup final in Toronto in August and in the match, Serena was forced to retire with a back injury.
Earlier in the day, Serena defeated Elina Svitolina 6-3, 6-1 to enter the finals of the tournament.
The finals of the US Open between Serena and Andreescu will take place on Sunday, September 8.