Celebrities such as actor Bill Murray and singer Huey Lewis have established a high profile at the Pebble Beach National Pro-Am but no one will command a greater share of the spotlight this week than defending champion Phil Mickelson.

Fresh from a scintillating display of dominant golf at the Phoenix Open where he clinched his 41st PGA Tour victory by four shots on Sunday, Mickelson returns to the picturesque surrounds of Pebble Beach Golf Links close to the best form of his career.

The American left-hander has long been renowned for his magical short game and exciting shot-making but he is especially excited by his much improved accuracy since acquiring a new driver which he put into play for the first time last week.

US golfer Phil Mickelson reacts to missing a birdie putt on the 10th hole of the north course at Torrey Pines during first round play at the Farmers Insurance Open in San Diego, California, Jan 24, 2013. [Photo/Agencies]

"It just changed my whole deal," a beaming Mickelson told reporters after closing with a four-under-par 67 on the Stadium Course at the TPC Scottsdale.

"The fact that this club is so easy to hit now, I think it's going to change the rest of the year for me. I really do.

"My iron play has always been the strength of my game ... but to drive it as easily as I did in play and to have the misses be so much less is going to set up for a very good year, I believe."

Armed with his new Callaway RAZR Fit Xtreme driver, four-times major champion Mickelson pounded the ball long and straight for most of the week at Scottsdale, and came within a whisker of shooting a 59 in the opening round.

"To be able to make a driver that spins this low with this much loft for me has never been done," said the 42-year-old, who had previously used a less-lofted model while adopting a more upward swing plane.

"Now I'm able to make the same golf swing as my irons. It really could be a revolutionary club for me."

Victory charge

Twelve months ago, Mickelson charged to victory by two shots at Pebble Beach after firing a flawless eight-under-par 64, and he is delighted to be back on the picturesque Monterey Peninsula as he bids to win the pro-am celebrity event for a fourth time.

"It's one of my favorite places to play golf," said the world number 10. "It's just a special week."

The $6.5 million event will be played on three courses: the hosting Pebble Beach Golf Links and its sister venues Spyglass Hill and Monterey Peninsula Shore.

"I'm a big fan of the addition of the Monterey Peninsula," Mickelson said. "It's one of my favorite golf courses anywhere in the world now and what a great addition it's been to go along with Pebble Beach and Spyglass Hill.

"We play three of the most amazing golf courses on tour and all combined in one week."

Mickelson faces a strong Pebble Beach field which includes two other members of the world's top 10 - sixth-ranked American Brandt Snedeker and Englishman Lee Westwood (eighth), who will make his first PGA Tour appearance of the year.

Also competing are triple major champion Padraig Harrington of Ireland and long-hitting American Dustin Johnson, tournament champion in 2009 and 2010.

An impressive list of celebrities for this week includes actors Ray Romano, Andy Garcia and Chris O'Donnell, musician Kenny G, National Hockey League great Wayne Gretzky and Green Bay Packers quarterback Aaron Rodgers.

The Pebble Beach National Pro-Am, the sixth event on the 2013 PGA Tour, starts on Thursday.