LONDON — Rafael Nadal looked hampered by his injured knees during a 6-4, 6-3 loss to Lleyton Hewitt in an exhibition Thursday. He will decide today if he can defend his Wimbledon title.

Nadal played without tape on his knees but frequently appeared a step slow in the grass-court match at Hurlingham Club. This was Nadal's first match since his loss to Robin Soderling in the fourth round of the French Open. He pulled out of last week's grass-court tournament at Queen's Club to rest his knees.

Nadal looked increasingly frustrated against the hard-serving Hewitt, repeatedly failing to get to balls he normally reaches and struggling with unforced backhand errors. He frequently muttered to himself in Spanish after missed shots and often had to rely on his top-spin forehand to escape trouble.

He did not speak to reporters, but uncle and coach Toni Nadal said it was still uncertain whether he can play at Wimbledon, which starts Monday.

Nadal plays another match today against Stanislas Wawrinka. Toni Nadal said the top-ranked player will decide after that. When pressed about Wimbledon, the coach did not sound optimistic.

"If it's me, I'm (flying) to Mallorca," he said, referring to the island where Nadal grew up.