World No. 1 Rafael Nadal has withdrawn from the Queen's Club Championships for the third consecutive year.
After winning the French Open at Roland Garros for an 11th time, Nadal had been due to begin his grass court season at Queen's ahead of Wimbledon in July.
"I have spoken to my doctors and need to listen to what my body is telling me," the Spaniard said.
"I would like to say sorry to the tournament organisers and the fans that were hoping to see me play."
Andy Murray is also a major doubt for the tournament. He has not played since Wimbledon last year, and he is yet to confirm whether or not he will appear at Queen's.