By Mark Lamport-Stokes

PACIFIC PALISADES, California (Reuters) -

Red-hot Phil Mickelson, fresh from victory at the Pebble Beach National Pro-Am on Sunday, chipped in to birdie his last hole and grab a one-shot lead at the Northern Trust Open on Thursday.

On a tricky day of strong, gusting winds at Riviera Country Club, the American left-hander delivered a superb five-under-par 66 to finish a stroke in front of compatriots J.B. Holmes and Hunter Mahan.

American Jonathan Byrd, who played in the stronger gusts of the morning, and Swede Carl Pettersson opened with 68s while British world number one Luke Donald launched his PGA Tour season with a 70.

However, 30 players were still out on the course when play was suspended in fading light and they will complete the first round on Friday morning.

Of those, 2006 winner Rory Sabbatini of South Africa was closest to the lead at two-under par with one hole remaining.

Mickelson, champion here in 2008 and 2009, recorded six birdies and a lone bogey to replicate the scintillating form he unveiled in the final round at Pebble Beach where he closed with a flawless 64.

Having made his only mistake of the day at the par-three 16th, he was delighted to end his round with a 35-foot chip-in from just off the back of the green at the par-four 18th.

"It wasn't one I was really trying to make," four-times major winner Mickelson told reporters. "It was quick, it was downhill and I had to play about four or five feet of break.

"I was trying to get good speed and try to let it feed with the break. I got fortunate obviously that it went in."

"I left one or two (shots) out on 16 and 17, and you hate to have such a good round and let a few slide late," added Mickelson, who failed to birdie the par-five 17th. "To make that shot unexpectedly on 18 felt like I got one of those back."


U.S. Ryder Cup player Mahan, who like Mickelson played in the afternoon, surged into contention with a sizzling run of four consecutive birdies from the par-four fifth, his 14th hole.

"I hit it good all day, with just a couple loose swings. Other than that, it was very solid from tee to green," Mahan said after recording eight birdies, two bogeys and one double-bogey. "I put myself in good position all day to make putts.

"The last seven holes the wind started to die down progressively, and by the end, it couldn't be playing any nicer or any better, so I was excited to come make some birdies late."

Big-hitting Holmes had even more reason to celebrate his first-round charge as he is playing in only his fourth PGA Tour event since having brain surgery last year.

The American returned to competition at last month's Farmers Insurance Open in San Diego, having been sidelined since August after being diagnosed with Chiari malformation, structural defects in the part of the brain which controls balance.

"It feels great to get out here and put in a good round right off the bat," the 29-year-old said on a day of winds gusting up to 35 mph through the Santa Monica Canyon.

"I made a bunch of birdies, a few mistakes, but overall it was a very good round for me, especially in these conditions.

"It was really difficult. We got about four holes where the wind wasn't blowing. It was whipping most of the day on us.

"I'm probably not quite 100 percent, but I definitely feel a whole lot better with my swing and my game and everything right now than I did at San Diego for sure."

(Reporting by Mark Lamport-Stokes; Editing by Frank Pingue/Ian Ransom)