Mickelson is usually a thrill-a-minute a guy who keeps everyone entertained by trying to hit clutch shots along the back nine with the tournament at stake. He birdied five of his last seven holes to win the Masters last year. He once hit a tee shot into the canyon during a play-off at Torrey Pines and still managed to win with a double bogey.
That's what makes these last two weeks on the PGA Tour so alarming.
One week after winning in Phoenix by a career-high five strokes, Mickelson went wire-to-wire in the Pebble Beach National Pro-Am to win by four strokes over Mike Weir.
"He's obviously doing something right," Weir said.
Mickelson has won his last two tournaments by nine shots. Going into this year, he had won his previous eight PGA Tour titles by a combined nine shots.
"After working on the right things now for a year, after getting back my distance off the tee and being able to utilise my wedge play, I feel like I'm able to make a lot more birdies," Mickelson said. "It just seems like ... I don't want to say the game is easier, but it just feels a little bit easier."
Mickelson closed with a one-over 73, the first time he has ever won with a final round over par. About the only thing he didn't get was the 72-hole record. He missed a 15-foot birdie putt on the final hole and finished at 19-under 269 one shot short of the record set seven years ago by Mark O'Meara.
Winning by such a large margin is new territory for Mickelson, and it might take some getting used to.
"It was weird," he said. "I didn't feel the normal intensity, the normal stress. It was a very enjoyable round." Which type of victory does he prefer? "I enjoy the stress-free day at Pebble Beach, playing with friends," he said, alluding to Ford president Steve Lyons, with whom Mickelson has an endorsement deal. "But I also enjoy that intensity and nervousness and the excitement of having to pull off clutch shots to win."
Mickelson became the first player to go wire-to-wire at the AT&T Pebble Beach National Pro-Am over four rounds, and it was the first time in his career he had led from start to finish.
He earned $954,000 for his 25th career victory, pushing him over $2 million and atop the PGA Tour money list. Mickelson is taking next week off, and will return to the Match Play Championship at La Costa.
Greg Owen of England, a PGA Tour rookie playing in the final group with Mickelson, birdied the last hole for a 72 and finished third to earn $360,000. Paul Goydos and Tim Clark each shot 71 to finish another shot back. For Goydos, it was his highest finish in six years.
Ireland's Darren Clarke carded a 71 to finish in a tie for sixth spot, eight shots back. Clarke turned in one-over-par 37 but fired two birdies on the inward nine. Graeme McDowell also posted his fourth successive sub-par round, with four birdies in a 71 leaving him one further back at 10-under in eighth place.
Paul McGinley, who began with rounds of 69, finished with a 73 to tie for 30th.