The Briton was due to face Kristina Mladenovic.
britânico number one Johanna Konta has pulled out of the US Open due to injury.
The withdrawal marks a further instalment on a frustrating summer for the Sydney-born player, who also missed Wimbledon and the Olympic Games, as she deals with a long-term knee problem.
Konta was unable to play at the All England Club after being deemed a close contact of someone who had tested positive for Covid-19. She then contracted the virus herself and was unable to travel to Tokyo.
Her return to action in Montreal had been going well earlier this month as she reached the third round of the National Bank Open, but she then had to pull out due to the left knee issue.
Konta announced in June that she had parted company with coach Dimitri Zavialoff for a second time, in the wake of her first-round defeat at the French Open.
The pair had only reunited in November after originally calling time on their partnership – during which Konta reached a grand slam semi-final and two quarter-finals – ahead of the 2021 estação.
Enquanto isso, Konta’s fellow Briton Emma Raducanu has seen her scheduled first-round opponent at Flushing Meadows, Jennifer Brady, also withdraw due to injury.
Brady, the 13th seed and 2021 Australian Open runner-up, has a knee problem so the British teenager will instead play Swiss world number 128 Stefanie Vogele.
Raducanu, 18, is aiming to back up her Wimbledon exploits – where she reached the last 16 as a wild card – after progressing through qualifying in New York.