Rafael Nadal withdrew from the Aegon Championships at Queen's, insisting he has been told to rest ahead of Wimbledon.
The French Open champion was due to play at the ATP 500 event starting Monday, but has chosen to skip the tournament, citing tiredness.
Nadal, the 2008 winner at Queen's, enjoyed another tremendous clay-court season, capped off by securing a record 10th crown at Roland Garros.
But the 31-year-old's chances of success at the All England Club, and a 16th major title, appear slim after his decision to miss the grass-court lead-up.
"I am very sorry to say that I am not going to be able play Queen's next week," Nadal wrote on social media.
"I am sad to make this decision because I love Queen's, I won the tournament in 2008 and every time I reached the Wimbledon final it was after playing Queen's.
"I was hoping to take some days off and then be ready, but at 31, and after a long clay-court season with all of the emotions of Roland Garros, and after speaking to my team and doctors, I have decided my body needs to rest if I am going to be ready to play Wimbledon.
"Sorry to all the great fans in Britain and to the tournament organisers. I hope to see you at Queen's next year."
Nadal is a two-time Wimbledon champion, but the last of those successes came in 2010 and he has failed to go beyond the fourth round since 2011.