By Julian Linden
PEBBLE BEACH, California (Reuters) - Graeme McDowell emerged from a tightly packed field to snatch the early clubhouse lead in the U.S. Open on Friday while several top players battled with the challenging Pebble Beach course.
Big-hitting Dustin Johnson, who won the last two regular PGA Tour events at Pebble Beach, led the American charge as Tiger Woods struggled on the same course he ripped up a decade ago when he won the U.S. Open by a record 15 shots.
It was partly because of Woods's runaway victory in 2000 that tournament organizers decided to toughen up the layout for this year's championship by tightening fairways, extending the rough and building more bunkers to add to the unique natural hazards of the surrounding beaches and cliffs.
Woods shot a 72 despite struggling off the tee and with his putter. It was well off his best but was two shots better than his opening round 74 when he failed to make a single birdie.
He finished the day seven shots behind McDowell and, while he has never won a major from that far back, the world number one was still talking up his chances of a 15th major.
"I'm right there in the championship. I just need to make a few more birdies, a few more putts on the weekend and I'll be right there," said Woods.
U.S. Masters champion Phil Mickelson, who could overtake Woods as the world's number one player on Sunday, started his second round late but immediately charged up the leaderboard with five birdies on the front nine to reach one-under.
McDowell, his confidence soaring after he recently won the Wales Open, made six birdies, including two putts over 20 feet, but also three bogeys, including one at his last when he led by three to give him his best chance yet of winning a major.
"I'd be lying if I hadn't thought about picking up the trophy on Sunday afternoon," said McDowell "I think that's only natural but I'm trying to be very realistic about it."
"It's almost links golf on steroids, with the rough and the grass around the bunkers," he said. "I needed a round like today to get me back in the tournament."
Ishikawa provided another demonstration of why he is regarded as one of the hottest talents in golf with two late birdies in a round of 71 that left him tied for second.
Playing in his first U.S. Open and being followed by a huge Japanese media contingent still buzzing about his 58 in May, he was given the royal seal of approval from his 60-year-old playing partner Tom Watson.
"He reminded me of me when I was 18," said Watson, who won eight majors, including the 1982 U.S. Open at Pebble Beach.
The three overnight leaders all dropped back through the field after starting the day at two-under.
Conditions were almost perfect when the early groups teed off with the greens slowed down by overnight watering and only a gentle breeze blowing in from the Pacific Ocean.
But none of the players could really take advantage with the cutoff projected to be as high as seven-over after the top professionals were made to look like weekend hackers.
Casey lost his place at the top of the leaderboard with a triple bogey on the 590-yard 14th while at least three players were forced to climb down the cliffs and play shots from off the beach.
(Editing by Frank Pingue)