"We will see on Monday or Tuesday," Nadal's coach, Toni Nadal, said on French radio RMC, Reuters reported. "We will go to Barcelona to see what the problem is. I am not too optimistic.
"Of course, if there is a possibility for him to take part in one the world's greatest tournaments, he will.
"He is very affected by this."
“I have been having some problems in the past months with my knees, that’s no secret, that did not allow me to compete always at 100 percent,” Nadal said in a statement released by the Queen's Club organizers. “I need to work with my team to recover well, work on my physical condition to be at my top form and get ready for the grass to play at Wimbledon. I hope I can be ready to compete by then.”
Wimbledon starts June 22.
On Sunday, Nadal lost in the fourth round of the French Open to Sweden’s Robin Soderling. It was the first loss at Roland Garros for the four-time French Open champion.
Nadal was also coming off a loss to Roger Federer in the final of the Madrid Open.
Nadal has played at the Queen’s tournament in west London every year since his first appearance in 2005. He won the title last year, beating Novak Djokovic 7-6 (6), 7-5 in the final.
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