World number 11 Milos Raonic is the latest high-profile player to pull out of the US Open, which starts on Monday.
Canadian Raonic has withdrawn because of a persistent wrist injury but said he planned to return to action before the end of 2017.
Defending champion Stan Wawrinka is unable to defend his title at Flushing Meadows because of a knee injury.
Novak Djokovic and Victoria Azarenka will also be absent.
World number 10 Kei Nishikori is also out.
