Carlos Alcaraz withdrew from the Madrid Masters on Friday, increasing concerns over whether he will be able to defend his Roland Garros title.
The world No 2 played in the Barcelona Open first round before pulling out of the tournament on Wednesday because of a wrist injury.
"There is news that is incredibly hard to share. Madrid is home, one of the most special places on the calendar for me, and that's why it hurts so much not to be able to play here for the second year in a row," wrote Alcaraz in a post on X.
"It especially hurts not to be able to be there in front of my people, at a tournament that is so special."
Earlier on Friday, 24-time Grand Slam winner Novak Djokovic also pulled out of the Madrid Open, which begins on 21 April.
The French Open, which Alcaraz won back-to-back in 2024 and 2025, starts on 18 May.
Alcaraz lost his world No 1 ranking following his defeat by Jannik Sinner in the Monte Carlo Masters final on Sunday.
He would have had a chance to regain it by winning the title in Barcelona, with Sinner not playing this week.
The 22-year-old Spaniard became the youngest man to complete the career Grand Slam in January with his triumph at the Australian Open. He holds a 22-3 record this season and also won a title in Doha.
Alcaraz said earlier this month he was hoping to play a full season on clay before starting his French Open title defence in late May.
Last year, he won in Monte Carlo but skipped the Madrid Open, returning in Rome to lift the trophy there for the first time.