Emma Raducanu has pulled out of the Chicago Fall Tennis Classic – her first scheduled appearance on court since winning the US Open.
The reason for the Brit's decision to withdraw has not been specified, but fans will have to wait a little longer to see her return to action.
The Chicago 500 event is scheduled to get underway on September 27th and run until October 3rd.
Raducanu has achieved almost unthinkable success – rising more than 300 places in the world rankings in just three months.
After making her WTA tour debut at the Nottingham Open in June, the 18-year-old went on to impress at Wimbledon before making history in New York as the first British woman to win a major tournament since Virginia Wade in 1977.
The world number 22 also became the only qualifier, male or female, to reach and win a Grand Slam final.
She beat Leylah Fernandez 6-4, 6-3 in a thrilling final at the Arthur Ashe Stadium, taking the crown from former world number one Naomi Osaka as US Open champion.
Raducanu's next scheduled appearance is set for October 6th at the BNP Paribas Open at Indian Wells. This tournament is viewed as one of the biggest non-slam events on the WTA tour and the Brit will almost certainly come up against some of the world's best players.
The Chicago Fall Classic will get underway next week, featuring world number four Elina Svitolina of Ukraine.
Sofia Kenin, Coco Gauff, and US Open semi-finalist Aryna Sabalenka have also withdrawn from the tournament, which is being listed as a WTA event for the first time this year.
The first match will get underway on Monday, September 27th. Svitolina is the top seeded player due her ranking, with the rest of the top five seeds consisting of Spain's Garbiñe Muguruza, Czech star Petra Kvitová, Switzerland's Belinda Bencic, and Maria Sakkari of Greece.