Brian Keogh in Los Angeles

Padraig Harrington continued to battle the gremlins in his game but still declared himself happier with his progress after a one-over par 72 left him nine strokes adrift of a rampaging Phil Mickelson in the Northern Trust Open at Rivera Country Club.

The Dubliner was wayward off the tee at times and erratic with his irons as he racked up five bogeys against four birdies on picture perfect day for scoring.

But his efforts looked very modest indeed as defending champion Mickelson regained his short game touch to scorch round in eight-under par 63 and lead by stroke in the clubhouse from American Scott McCarron with Dean Wilson, Jim Furyk, Luke Donal and Pebble Beach winner Dustin Johnson two shots further back after rounds of 66.

"It was better,” said Harrington, who was frustrated not to hole anything outside eight feet. “I've been working on the putting but that was the weakest part of it to be honest. I had 27 putts but I don't really worry about how many putts I take. It’s about how many I hole and I certainly didn't hole too much.”

The reigning Open and US PGA champion has been flummoxed by elements of his long game in recent weeks but he was happier yesterday in the sense that he knew where the bad shots were coming from

"I should have been where I am now two weeks ago, but that is about it,” he said. “I was a lot happier about how it went today because I could understand why every shot went where it did. Nothing surprised me. I just didn't hole too many putts and didn't get many breaks either, especially on a couple of chip shots.

"These things happen but I am lot happier with my game today because this is where I would have expected to be two weeks ago. I am a lot happier than I have been at any stage over the last two weeks."

Starting on the signature 315-yard 10th, Harrington was short sided 15 yards from the pin and two putted from 22 feet for his par before picking up his first shot of the day at the par-five 11th with a wedge to eight feet.

But there were early signs that his focus is not quite where it should be and after a pushed drive and a fluffed pitch led to a bogey at the 12th, he bunkered his tee shot at the short 14th to creep over par and struggled for long periods after that.

After failing to birdie the par-five 17th, where his wedge spun back off the green, he pulled his approach to the 18th and missed an eight footer for par when his delicate chip looked destined to hit the pin but scuttled on down the hill.

A birdie at the downhill, par-five first helped him keep pace with the field but he was forced to chip out of the trees after a pushed drive at the second and followed that with another bogey at the third, where he pulled his drive 20 yards wide of the fairway before almost holing in one at 236-yard fourth, where his hybrid tee shot finished 18 inches from the hole.

He then hit an eight iron to four feet at the eighth but his play - especially in the short game department - looked positively pedestrian by comparison with that of Mickelson, who broke 70 for the first time this season in spectacular fashion.

Harrington had dinner earlier this week with Holywood actor Dennis Hopper of Easy Rider and Blue Velvet fame. But it was his dinner date at Mickelson’s 6,000 square foot Rancho Santa Fe mansion during the Buick Invitational at Torrey Pines, that really caught his interest.

When Harrington looked around the home of the biggest name in golf after Tiger Woods, he was amazed to see the head of an authentic, 65 million year old Tyrannosaurus-rex sitting on a plinth in the living room - a Christmas gift from his wife Amy. What else do you get the man who has everything?

The left-hander was certainly playing in a different time zone to Harrington yesterday after a less than stellar start to the season - missed cut, tied 42nd and tied 55th.

Playing in the group immediately behind the Dubliner, the world number five made four birdies on each nine and his short game was so good after some recent work with Dave Pelz that he used the blade just 22 times.

“It was obviously a good round,” Mickelson said. “But I didn’t feel that I played immaculate. I still feel as though it’s coming. The reason why the score was so low is I ended up making some putts. I holed a chip and got up and down on every green that I missed, which is very helpful.

“I think I missed six greens and ended up playing those holes in one under, so that was a good area for me to keep the round going when I did mis-hit a shot.”

Late starter Graeme McDowell was one-under par after nine holes of his opening round.

Starting on the back nine, the Portrush native birdied the par five 11th and then sandwiched a birdied at the short 14th between bogeys at the 13th and 15th before picking up a shot at the par-five 17th.