Padraig Harrington struggled with his putting as he opened with a disappointing, two-over-par 74 at the AT&T Pebble Beach National Pro-Am in California.

The world No 3 took 37 putts and finished the opening round nine shots behind leaders Robert Garrigus and Dustin Johnson with fellow Dubliner Paul McGinley seven strokes off the pace after a level par 72.

Starting on the back nine at Poppy Hills, Harrington bogeyed the par-three 11th but then birdied the par-five 18th to turn in level par. But he dropped three shots in a row from the second to slip to three-over before repairing some of the damage with a two-putt birdie at the par-five ninth.

Harrington struggled with his long game in last week's Buick Invitational at Torrey Pines, spending so much time working on finding a cure for a hook that he confessed that he neglected his short game.

At Poppy Hills he missed just one fairway and only three greens but failed to make anything with the putter.

McGinley turned in two-over after three bogeys and a birdie but came home in level for his 72 thanks to birdies at the par-three sixth and the ninth.

Padraig Harrington with JP McManus at Adare Manor in 2005.

In the pro-am stakes, Harrington's partner JP McManus helped the team card a three-under par 69 with McGinley and Dermot Desmond posting a 70 that left them tied 114th and 142nd respectively.

Garrigus carded a 65 at Spyglass Hill with 2007 Walker Cup star Johnson matching him at Pebble Beach to lead by a shot from Rich Beem, Vaughn Taylor and Charley Hoffman. World No 4 Vijay Singh shot 72 at Poppy Hills on his return to action after knee surgery and is tied for 90th with McGinley and world No 5 Phil Mickelson, who shot his level par 72 at Spyglass Hill.