Juan Martin del Potro will not compete at this year's US Open as the 2009 champion continues to recover from a knee injury, tournament organisers said on Tuesday.
The Argentine re-fractured his kneecap during the Queen's Club Championships in June in the latest setback to his injury-plagued career.
The world No 12 missed Wimbledon after scans revealed he had fractured his right patella and he underwent surgery.
Since his triumph at Flushing Meadows in 2009, Del Potro has had three left wrist surgeries and another to his right wrist but he has fought back each time to return to the ATP tour.
He reached last year's US Open final and won the Masters 1000 event at Indian Wells in 2018 but had said on social media that he's not sure if this latest injury could mean the end of his career or not.
Del Potro will be replaced in the main draw at Flushing Meadows by the American Denis Kudla and the Grand Slam's draw will take place on August, 22.
The wild card that was previously allocated to Kudla will go to the 23-year-old American Chris Eubanks whilst Cori Gauff headlines the women's singles wild cards.