MONACO — Rafael Nadal pulled out of the clay-court Monte Carlo Masters on Tuesday, saying he is not yet able to compete at the highest level.

The 22-time Grand Slam champion has been sidelined with a left hip flexor injury since the Australian Open. The Monte Carlo Masters begins on April 8.

“I will not be able to play in one of the most important tournaments of my career, Monte Carlo,” Nadal wrote on Twitter. “I am not yet in conditions to play with the maximum guarantees and I continue my preparation process, hoping to be back soon.”

Second-ranked Carlos Alcaraz and seventh-ranked Felix Auger-Aliassime also withdrew from the event.

Alcaraz pulled out because of “physical discomfort” after his semifinal loss in Florida last week. The Spaniard had been so dominant recently, he hadn’t lost a set since February before that defeat.

“I have post-traumatic arthritis in my left hand and muscular discomfort in the spine that needs rest to prepare for everything that is to come,” the 19-year-old from Spain said.

Auger-Aliassime needs to rest his left knee.

“I have been struggling with my left knee for the past few weeks and decided it was the smartest decision to take some time off so I’m able to fully heal and recover,” the 22-year-old Canadian wrote on Instagram.

Nadal has won the Monte Carlo tournament a record 11 times, including an Open Era record streak of eight consecutive titles from 2005-12. The 36-year-old Spaniard generally uses the event as a key part of his preparations for the French Open, which takes place May 28-June 11.

Nadal has won 14 of his major titles on clay at Roland Garros, including last year while dealing with chronic pain in his left foot.

In January, Nadal hurt his hip flexor during a second-round loss to Mackenzie McDonald at the Australian Open.