Luke Donald insisted he was "satisfied" with his opening two rounds at the US Open after he set the early clubhouse target at level par.
As scores soared at the brutally-tough Merion Golf Club, Donald completed a first-round 68 early on Friday morning before adding an erratic 72 in his second round.
The former world No 1 birdied two of his first three holes in his second effort after starting on the 11th, and he followed at bogey at 15 with a good run of four pars.
But he then paid the price for failing to avoid the punishing rough as he bogeyed five of the next six holes, including ugly sixes at the par-five second and fourth.
However, Donald clawed a shot back at nine and parred the next to take the clubhouse lead, although he was soon overtaken after Billy Horschel fired a superb 67 to get in at one under.
"I was upset at the par fives. To make two sixes there was bad golf, poor management," he said. "But overall I'm pretty satisfied with the last two days.
"I think Merion is holding its own, for sure. It's not really firming up, but there is enough breeze to make it tricky. It's hard to make a lot of birdies.
"The pins were a lot more tucked. They were difficult to get to. I didn't play the par-fives well, but the other bogeys I didn't feel I made too many mistakes. It's just a tough golf course.
"The greens are soft enough that controlling that spin is tough and it's hard to make a lot of birdies so I'm happy to have made my share over the last two days.
"Anything around par is pretty good and US Opens don't tend to get easier as the week goes on - it's a grind out there."
When asked how he responded after his horror run on the front nine, Donald added: "You try not to panic in US Opens. You are going to make mistakes. I've got to minimise those mistakes over the next two days.
"I'm excited to be in contention. Obviously I haven't played very well in the US Open before, but when I saw this place last week I thought it was a good fit for my game.
"And obviously it's nice to come here and feel like I'm swinging pretty well and I've got a chance."