World No. 11 Khachanov has delayed his return to the court after suffering a stress fracture and a partial fracture in his sacrum S1 bone during the French Open earlier this year.
The Russian has not competed in singles since the Roland Garros, where he reached the quarter-finals before being defeated by eventual champion Novak Djokovic.
Doping drop: Halep down more than 500 spots in a single week in WTA Rankings awaiting tribunal
Khachanov forced to miss Wimbledon
Last month, Khachanov announced he had been forced to withdraw from Wimbledon because of his injuries.
"Due to an unfortunate injury I picked up at the French Open(stress fracture and a partial fracture in sacrum S1 bone), I will not be able to participate at Wimbledon for the second year in a row," he wrote.
"The decision to withdraw was not an easy one and i was [hoping] till the end during these few weeks that I would be able to recover however my medical team ensured me that in my case it wasn’t possible," he added.
"It's strange that the people don't care so much about us": Samsonova frustrated after being forced to play two matches in one day in Montreal
More setbacks for Khachanov
Khachanov continued his post by writing of how he was focusing on recovery in an attempt to return to tournaments in August.
"As difficult as this is, I will now focus on my recovery, working diligently to get healthy and come back to tournaments in August. Meanwhile I am happy that I have my family by my side and grateful that I can be present for the birth of my second son who we are expecting really soon.
"I remain committed and will use this setback as motivation to come back and hopefully keep achieving as I wish to do," he wrote.
However, the 27-year-old now faces further setbacks ahead of the upcoming US Open with his recent withdrawal from Cincinnati.
He was originally meant to face Andy Murray in the Round of 64, but after the Briton also withdrew due to injury, he was set to play against Daniel Altmaier, who is now going on to play fellow lucky loser Alexei Popyrin instead.
Despite withdrawing from singles, Khachanov played at the tournament yesterday in doubles, where he and Robin Haase defeated Dan Evans and Andreas Mias.