Harrington, the 2006 European number one, carded 10 birdies

FIRST ROUND LEADERBOARD:
(US unless stated)
-8 Padraig Harrington (Irl)
-5 Phil Mickelson, Pat Perez, Briny Baird
-4 Kevin Stadler, Sergio Garcia (Spa), Jim Furyk, David Howell (Eng), Cameron Beckman
-3 Aaron Baddeley (Aus), Vijay Singh (Fij), Rodney Pampling (Aus), Eric Axley, Geoff Ogilvy (Aus)

Padraig Harrington shot a superb eight-under-par 63 to take the first-round lead at the Nissan Open in Los Angeles on Thursday.

Playing the event for the first time, he shot 10 birdies and two bogeys to card his lowest score on the PGA Tour.

The Irishman needed just 26 putts to complete his impressive round.

Harrington finished three shots clear of Phil Mickelson, Pat Perez and Briny Baird, with David Howell, Jim Furyk and Sergio Garcia a further shot back.

And Fiji's Vijay Singh was among five players on three under in a high-class field at the Pacific Palisades course. England's Luke Donald, however, struggled, ending his round four over.

"Some day it will catch up on me, the fact I don't know the golf course - today it didn't," said Harrington, who won the European Order of Merit last year.

It is a little humbling to shoot what I thought was a good round and then get lapped by three Phil Mickelson

"It's only Thursday, so it's a good round of golf - if it was on a Sunday to win, it would be a great round. But on a Thursday it's a good round, it's a 63, but nothing more than that.

"It's a tight golf course with a lot of difficult pin positions and I will make mistakes between now and the end of the week."

Pre-tournament favourite Mickelson, who captured his first victory of 2007 at the Pebble Beach Pro-Am on Sunday, was certainly impressed by Harrington's effort.

"I thought that was an incredible round. He had some good putts because a lot of the pins were tough to get at," said the American left-hander.

"It is a little humbling to shoot what I thought was a good round and then get lapped by three."

Ernie Els, the world number five, is among a host of players who opened with a two-under 69, one shot better than popular American John Daly and Spain's Jose Maria Olazabal.

Els's compatriot Retief Goosen, ranked sixth in the world, is on level par after a 71, while Australia's Adam Scott, the world number three and 2005 champion here, posted a one-over 72, the same score as England's Justin Rose.

Rose's fellow Englishman and good friend Ian Poulter, however, endured a difficult day as he stumbled to a six-over 77.

Paul McGinley is among six players who will have to finish their first rounds early on Friday. The Irishman is one under with two holes to play.

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