Harrington opens with 75 at Northern Trust Open

A run of five bogeys in seven holes ruined any chance of Pádraig Harrington making an early impression at the Northern Trust Open in California as he signed for a four-over-par 75 in his opening round at the Riviera Country Club.

Things had started well for the Dubliner with birdies on the par-five first and the third hole putting him among the early leaders. His first bogey would come at the par-three fourth before a run of three straight bogeys from the seventh pushed him out to two over.

Back to back dropped shots on the 12th and 13th and a three-putt from 10 feet on the par-five 17th for bogey left Harrington on five over before a closing birdie on the 18th came when he rolled in a 17-foot putt for a three.

Darren Clarke withdrew from the tournament with the recurrence of chest muscle injury after he struggled his way to an opening round of 78. The injury also prevented the Ulsterman playing in the recent Qatar Open.

At the other end of the leaderboard, Dustin Johnson seized the first-round lead after an impressive 66 gave him a slender advantage.

The 29-year-old American was five under after 10 holes but dropped a shot on the fourth, his 13th, before regaining it on the penultimate hole.

That was enough to give him a one-shot lead over a group of 11 players all on four under, including Johnson's fellow Americans Jimmy Walker, Robert Garrigus and Scott Stallings, Italy's European Ryder Cup star Francesco Molinari and Australian Matt Jones.

Walker and Johnson bring form to the tournament, having finished first and second last week at the AT&T Pebble Beach National Pro-Am.

Leader Johnson said: “I’ve been playing pretty good all year, so the game’s right where I want it to be.

“Coming off a good week last week, I’m definitely feeling good coming in this week and then obviously getting off to a great start. Any score under par out here is a pretty solid round. It’s a tough course, but it’s right in front of you, so it’s just a golf course that I really like.”

Leading European Molinari said of his round: “It was all pretty good. I had a good start and I like the way the golf course is playing. I’m pretty good usually at keeping the ball in position and made a few nice putts. So (it was a) very good start to the tournament.”

American veteran Jim Furyk was a further shot back after firing a 68, joined on that mark by compatriots Keegan Bradley and Rickie Fowler.

South Africa's 2011 Masters winner Charl Schwartzel, England's former world number one Lee Westwood and South Korean KJ Choi all finished their opening rounds on two under, one ahead of US Open champion Justin Rose, Hunter Mahan and former British Open champion Ben Curtis. Ian Poulter had a disappointing day as he shot a one-over-par 72.