Tiger Woods appeared to be troubled by a wrist injury as he made an uncertain start to the US Open at stormy Merion.
The world No 1 offset two birdies with four bogeys over the first 10 holes, and he elected not to attempt a three-foot par putt on the 11th green as the light faded after a day curtailed by bad weather.
Woods looked to have jarred his left wrist after hacking out of deep rough following a blocked tee shot on the opening hole.
He winced in pain again after punching out of rough at the fifth, although he did not mention the problem when interviewed on his way to the clubhouse.
"It's going to be a fast night," said Woods, who will resume his first round at 7.15am (local time) on Friday. "I've got a lot of holes to play, and hopefully I can play a little better than I did today."
Woods, who is six shots behind leader Luke Donald, refused to blame the weather disruptions for his poor start after play was delayed by three-and-a-half hours early on and by a further 45 minutes later in the day.
"It's kind of the way the tour has been this year," Woods added. "We've had a lot of bad weather this year and this is the way it has been."