Novak Djokovic is still working through the injury problems that forced him to miss recent events in Miami and Monte Carlo and says he may not be ready for next week's Madrid Open, one of the last stops before the French Open Grand Slam.
The 38-year-old Serb lost to Carlos Alcaraz in the Australian Open final in February and fell to Jack Draper in the Indian Wells fourth round last month, before pulling out of the Miami Open due to a right shoulder injury.
The 24-times Grand Slam champion then skipped last week's Monte Carlo Masters before arriving in Spain to begin preparations for the April 22-May 3 Madrid Open.
However, his participation at the event, which he has won three times, remains in doubt.
"I hope to compete here, I'm working towards that," Djokovic told Spanish broadcaster Movistar+ at a EuroLeague basketball game in the Spanish capital on Thursday.
"I don't (know), I'm not sure. I have been struggling physically a little bit with an injury, so I'm trying to address that and play as long as I can.
"Now I have a little bit more time, not playing as much, so I get a chance to enjoy other sports and great athleticism,” Reuters quoted him as saying.
The draw for the Madrid Open will be held on Monday.
Djokovic will be looking for a record 25th Grand Slam title when Roland Garros gets underway on May 24.