Rafael Nadal's Wimbledon preparations suffered a blow on Friday when he had to retire from his Stella Artois quarter-final in London against Australian Lleyton Hewitt with a shoulder injury.
The double French Open champion had taken the first set impressively 6-3 but needed treatment to his left shoulder in the second which he lost 6-3.
Nadal, the tournament's top seed, then told the chair umpire that he did not want to continue at the start of the third set and will now face a race to be fit for the grasscourt Grand Slam which begins on June 26.
"I felt a lot of pain here," Nadal told reporters afterwards, indicating the point of his left shoulder. "It's a shame because I was playing my best match [on grass] here today."
Asked if he thought he would be fit for Wimbledon, the world number two replied: "I don't know, I hope so."
The 20-year-old Mallorcan, who beat Roger Federer to win his second French Open in a row on Sunday, said he hoped to fly home later on Friday to consult his physio.
"He said it was his shoulder. I said, 'That's what happens when you play so many matches,'" said a sympathetic Hewitt, who faces Briton Tim Henman in the semi-finals.
Nadal's defeat ended his run of 26 consecutive wins since his defeat by Carlos Moya at the Miami Masters in March.
Henman broke his jinx against Dmitry Tursunov by beating the Russian 6-3, 7-6.
He was knocked out of Wimbledon by Tursunov last year and also lost to him at this year's Australian Open and French Open, but on Friday the Briton had the better of a scrappy encounter on the Queen's Club grass.
MONFILS INJURY
In the second set the four-times Wimbledon semi-finalist was a set point down. Tursunov, though, double-faulted and Henman rattled through the tiebreak 7-1, sealing victory with a big forehand.
"He's beaten me on a couple of big occasions and he's an awkward guy to play against, so it's good to get through and continue my form," said 31-year-old Henman.
"I feel good about my game. After struggling on grass the last two years I do feel much more comfortable."
Like Nadal, French teenager Gael Monfils also quit his quarter-final against American James Blake due to injury.
The 19-year-old had lost the first set 6-1 to Blake when he retired with a back injury. A tournament spokesman said Monfils would not play in next week's Nottingham grasscourt event.
Blake will play the winner of the last quarter-final between defending champion Andy Roddick and Chilean Fernando Gonzalez.
