Rafael Nadal has withdrawn from the Barcelona Open, saying he is "still not ready" to return to the men's ATP tour.
Nadal, 36, has been struggling with an ongoing hip injury that has also kept him out of this week's Monte Carlo Masters.
The 22-time Grand Slam winner remains a doubt for the French Open in May, where he is defending champion.
Nadal has not played since he was defeated by American Mackenzie McDonald at the Australian Open in January.
Writing on Twitter, the Spaniard said: "Barcelona is a special tournament for me, because it is my adopted club and because playing at home is always a unique feeling.
"I am still not ready and, therefore, I continue my preparation process for the return to competition."
The Barcelona Open, which Nadal has won 12 times, starts on Monday, and is one of the last big clay-court events before the French Open begins in Paris on 28 May.
Nadal, who is ranked 14th in the world, was diagnosed with a left hip injury after he was beaten in straight sets by McDonald in the second round in Melbourne.
The anticipated recovery time was six to eight weeks, but Nadal will not be back in action, at the earliest, until the Madrid Open, which starts on 25 April.
