Nadal withdraws from Rome Masters as French Open fears grow
The 22-time Grand Slam winner has not played since suffering a hip injury at the Australian Open in January.
The French Open, which the 36-year-old has won on a record 14 occasions, gets underway in Paris in three weeks' time.
Nadal said his injury situation has improved in the past few days but not sufficiently to be able to compete next week in the Italian capital.
"I am very sorry to announce that I will not be able to be in Rome," Nadal wrote on his social media accounts.
"You all know how much it hurts me to miss another of the tournaments that have marked my professional and personal career because of all the love and support of the Italian tifosi (fans).
"Although I have noticed an improvement in the last few days, it has been many months without being able to train at a high level and the process of readjustment takes a certain amount of time, and I have no choice but to accept that and continue working."
The 22-time Grand Slam champion - he shares the men's record with Novak Djokovic - had originally thought he would be out for up to two months.
He pulled out of hard-court tournaments at Indian Wells and Miami, with his sights set on a return at the start of the clay-court season, but it did not come to fruition.
Nadal had to withdraw from events in Monte Carlo, Barcelona and Madrid, before eventually adding Rome, the final French Open warm-up event, to the list.
