Russian world number two Daniil Medvedev says he will be out for one to two months after deciding to have surgery on a small hernia.
Medvedev, 26, missed out on a chance to return to the top of the world rankings when he lost to Poland's Hubert Hurkacz at the Miami Open on Thursday.
"The last months I have been playing with a small hernia," he said.
"Together with my team I have decided to have a small procedure done to fix the problem."
His statement on social media continued: "I will likely be out for the next 1 - 2 months and will work hard to be back on court soon.