Madrid (AFP) - Rafael Nadal and Carlos Alcaraz withdrew Tuesday from the Monte Carlo Masters, raising questions over their fitness ahead of next month's French Open.
Nadal is preparing for a tilt at a record-extending 15th French Open title -- and a 23rd Grand Slam crown, to break the men's all-time record he shares with Novak Djokovic.
"Hi everyone, I'm still not ready to compete at the highest level," the 36-year-old Nadal tweeted.
"I will not be able to play in one of the most important tournaments of my career, Monte Carlo."
Nadal has won the Monte Carlo tournament 11 times.
The French Open starts May 28.
Nadal said he was hoping to return soon from the hip flexor injury he sustained in the Australian Open in January, suffering a second-round exit against Mackenzie McDonald.
The Spaniard 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.
Record Monte Carlo Masters champion Nadal won the tournament eight consecutive times between 2005 and 2012.
After the tournament's director said Nadal was registered for this year's edition, the 22-time Grand Slam champion last week denied he was set to participate.
"I don't know who gets this information, but obviously if it were true, I would confirm it, but, unfortunately, I cannot confirm it," said Nadal at an event.
"Things are moving day by day, and I don't say things that I can't fulfil."
Nadal's announcement Tuesday was followed by that of Alcaraz, who pulled out of Monte Carlo because of hand and back injury problems.
"After two months abroad, I am happy to return home but sad because I finished my last match in Miami with physical discomfort," said Alcaraz on Twitter.
"I will not be able to go to Monte Carlo to start the clay court tour.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."
Newspaper Mundo Deportivo ran the headline: "Black Tuesday for Spanish tennis," after its top two stars withdrew from the first major event of the clay-court season.
Djokovic, who reclaimed the number one ranking from Alcaraz on Monday, will headline the field at Monte Carlo, which begins on Sunday.
The Serb missed tournaments at Indian Wells and Miami after he was unable to enter the United States because he is unvaccinated against Covid-19.
He hasn't played since losing to Daniil Medvedev in the semi-finals in Dubai at the start of March, a defeat which snapped his 20-match winning streak.