Two hours after he won the PGA Championship with a birdie on the fifth day and final hole, he found himself squeezed in every direction by nearly 100 fans who gathered around for autographs, creating a large circle of humanity that slowly moved toward the parking lot.
It has been that way for years. Winning doesn't change the way fans feel about their beloved Lefty.
But among his peers, the perception of Mickelson as a major force changed significantly.
His one-shot victory in the PGA Championship allowed him to break away from an underachieving class of players who finally won their first major and never captured another. And he joined an elite group of players who have won majors in consecutive years.
``He's not a one-major guy, he's a 10-major guy,'' Thomas Bjorn said. ``He's going to go on now and contend for majors as he's always done, but it's going to be easier and easier for him to win them now. And he deserves greatness.''
Mickelson still only has two majors -- same as Lee Janzen, John Daly and Mark O'Meara -- and predicting greatness is a dangerous business in golf. Who would have thought Davis Love III would still only have one major championship after his PGA victory in 1997?
Even so, Mickelson set himself apart from other rivals to Tiger Woods, who remains in a class by himself.
Vijay Singh, Ernie Els and Retief Goosen all have multiple majors since Woods arrived in 1997, although none has been able to sustain any kind of challenge in the tournaments that matter the most.
Singh has been on top of his game since winning the 2002 Tour Championship at East Lake, winning 17 times over the last three years. But when Woods went into a tailspin, the 42-year-old Fijian managed to win just one major, last year at Whistling Straits in a playoff.
Els rarely backs up a big year in the majors with another one.
After winning the 2002 British Open at Muirfield, he never contended in any of the '03 majors. And while he had a good shot at all of them last year, he again was never a factor this year until his season ended with knee surgery.
Goosen, whose game is slowly getting the respect it deserves, lost his chance to win consecutive U.S. Open titles -- only Curtis Strange has done that in the last 50 years -- when he shot 81 in the last round at Pinehurst.
That's what made Mickelson's victory at Baltusrol so big.
He joins Woods and Nick Faldo as the only players to have won majors in consecutive years since 1990.
Walter Hagen went six straight years winning at least one major (four in a row at the PGA Championship), while Jack Nicklaus and Woods each went four straight years with a Grand Slam trophy. Perhaps it is no surprise that they are the top three on the career majors chart.
Mickelson got off to a slow start.
It took him a dozen years on the PGA Tour and 22 victories to capture his first major last year at the Masters, and it appeared it might take him a while before he got his next one. Mickelson failed to contend in any of them this year, but he was determined the PGA Championship would be different.
And he was right.
Mickelson went back to that controlled cut off the tee to take the right half of Baltusrol out of play. He looked confident over putts that were 4 feet or 40 feet, and made enough of them that when the hole got smaller on the weekend, he still could afford to miss a few.
But he has some catching up to do.
``At 35, I've got a number of years left -- good years left -- where my game can continue to improve,'' Mickelson said. ``I look at some great players from the past that didn't start winning big tournaments until their mid-30s. I want to try to get better and better as my career goes on.''
Ben Hogan won eight of his nine majors after turning 35. Sam Snead won six of his seven majors at 35 or older. Nicklaus won his 18 majors over 25 seasons, with the last six coming after he turned 35.
There's still time.
The Wanamaker Trophy at his side Monday afternoon, Mickelson wasn't ready to consider the future. For years when the season ended without a major, he dreaded having to wait seven months for his next chance.
``The next major isn't for another seven months,'' Mickelson said, this time with a grin. ``I just want to relish this, and enjoy the fact that for the next seven months, I'm the most recent major winner.''
Still, Lefty can start entertaining thoughts of a career Grand Slam, the ultimate measure of greatness.
Els (U.S. Open, British Open) and Singh (Masters, PGA) already are halfway there, each capable at the majors they have not won. Ditto for Mickelson, especially since Baltusrol was set up like a U.S. Open, and his two runner-up finishes at majors have come in a U.S. Open.
It would seem the British Open would present the stiffest test, but how to explain Mickelson finishing one shot out of a playoff at Royal Troon last year? If he's playing well, he can win anywhere.
``There are different challenges to winning each major, and I'm pleased to have accomplished two of those challenges,'' Mickelson said. ``But there are two more that would show the complete player.''
With major victories in consecutive years, it could happen sooner than some people think.