Previously, 19-year-old Leylah Fernandez, Canada, and 18-year-old Carlos Alcaraz, Spain, have gone equally far in the women's and men's singles tournaments in this year's fourth and final grand slam tournament.
Raducanu - who was forced to break the round of 16 at Wimbledon in July with breathing difficulties - is an unseeded qualifier at the US Open.
She beat American home player Shelby Rogers in straight sets, 6-2, 6-1, in the round of 16 and is next set against the Swiss Belinda Bencic.
Eleventh-seeded Bencic answered for a small surprise when she beat last year's champion in the French Open, Iga Swiatek, Poland, in straight sets - 7-6 (14-12), 6-3 - in the US Open fourth round.
MORE TENNIS: Here Ymer throws the racket - and quarrels with the referee (1 Sep 2021)
Javascript is disabled
Javascript must be turned on to play video
Read more about browser support
The browser is not supported
SVT does not support playback in your browser.
We therefore recommend that you switch to another browser.
Read more about browser support
Mikael Ymer knocked out of US Open Photo: Eurosport