Fernandez booked her spot in the last four following an upset quarter-final win over Ukraine’s Elina Svitolina.
The Canadian teenager from Laval, Que., who celebrated her 19th birthday on Monday, overcame the 2020 Tokyo Olympics bronze medalist in a tight three-set battle that lasted two hours and 24 minutes.
She won with the scoreline of 6-3, 3-6, 7-6(5) against the fifth-seeded Ukrainian.
Fernandez will now face world number two Aryna Sabalenka of Belarus, who defeated Czech Barbora Krejcikova 6-1,6-4, for a spot in her first major final.
On the men’s side, it was a much shorter outing on court for Montreal’s Auger-Aliassime, who advanced to the last four stage after his Spanish opponent Carlos Alcaraz retired early in the second set due to a leg injury.
Auger-Aliassime, seeded 12, was leading 6-3, 3-1 when Alcaraz decided to call it quits after an hour and eight minutes of play.
The 21-year-old Canadian will next face Russian second seed Daniil Medvedev in the semi-final.
The year’s last Grand Slam in New York has become a happy hunting ground for Canadians.
In 2019, Bianca Andreescu stunned Serena Williams to lift the U.S. Open trophy, becoming the first Canadian to win a Grand Slam singles title.
Her 10-match unbeaten run in New York was snapped in the fourth round by Greek player Maria Sakkari in the latest finish of a women’s singles match at the tournament earlier on Tuesday.
Fernandez, currently ranked 73 in the world, had already upset Naomi Osaka of Japan in the third round and Germany’s Angelique Kerber in the fourth.
When asked what was behind the success of Canadian tennis players, she said, laughing: “I would say it’s the maple syrup. The Canadian maple syrup are very good.”