US Open organisers confirmed that women's singles semifinals were postponed to Friday due to forecasts of rain in New York.
The semifinals were scheduled for Thursday.
Top-ranked defending champion Serena Williams, who is seeking more tennis history, now will play Italy's 43rd-ranked Roberta Vinci in Friday's first semifinal, followed by Romania's second seed Simona Halep taking on Italian 26th seed Flavia Pennetta in the other semifinal, Xinhua reported.
The winners will meet in Saturday's final.
