The easiest place to begin any analysis of Phil Mickelson’s extraordinary victory Sunday at the PGA Championship is with this: He is now the oldest man in golf history to win a major championship. One month shy of 51, he surpassed Julius Boros, whose victory at the 1968 PGA Championship when he was 48 stood as the record for more than a half-century.

It’s worth mentioning that Boros broke a record that Old Tom Morris had held for 101 years. Old Tom won the British Open — the only major that existed in 1867 — when he was 46. Golf is, if nothing else, very old.

But there’s much more to Mickelson’s victory on the Ocean Course at Kiawah Island than just the “old guys rule” cliche.

It can be argued that no great player in history has been written off more often, and in more different ways, than Mickelson. He has been on the public stage since he won the Northern Telecom Open as an amateur in 1991 while still a junior at Arizona State. His arrival on the PGA Tour in 1992 was hyped as the arrival of a new golf savior. When he went eight months without winning, whispers began that maybe he wasn’t all that special.

Then, early in 1993, he won in his San Diego hometown. He kept on winning, accumulating 22 victories on tour over the next 11-plus years. But he didn’t win a major in that span, although he came close.

Tiger Woods arrived on tour in 1996 and more or less shoved Mickelson — and everyone else — into the background. By the end of 2003, Woods had won eight majors and was putting up numbers never before seen in the sport.

Mickelson was winning golf tournaments and making huge dollars from corporate America because he said all the right things, had a big smile and signed more autographs than any player since Arnold Palmer. Fans loved him; the media loved him. His fellow pros — not so much.

His locker room nickname was “Eddie Haskell” — the kid in the old “Leave it to Beaver” TV show who was always ultra-polite to Beaver’s parents and then, as soon as their backs were turned, led Beaver and older brother Wally into trouble.

Players said the smiling, friendly Phil the public saw was considerably different from the often-aloof Phil who drifted in and out of locker rooms. Mickelson was aware of the chatter.

Standing on the putting green at Royal Troon before the 1997 British Open, he talked about his image with other pros. “I get the way some guys feel,” he said. “The thing you have to understand is that [wife] Amy and I are 24/7. We’re together all the time. We like being together like that. She’s my best friend. She’s the person I want to hang out with the most.”

That was what I always found appealing about Mickelson — he had an honest streak when he was standing on a putting green and there weren’t microphones being thrust in his direction. He never resorted to the “I’ll have had a great career even if I never win a major” cop-out when he still hadn’t won one. Instead, he would look you in the eye and tell you that there was a hole in his résumé and that he wouldn’t feel satisfied until it was filled.

He finally got it done at the Masters in 2004, at a point when some people had already decided he would make lots of money playing golf but would never find greatness. He was a different guy by then. When someone asked him in a Saturday evening news conference how it felt knowing he was nine shots ahead of Woods, he didn’t go for the timeworn answer about how many good players he still had to beat, about going out and playing the golf course.

Instead, he smiled his impish smile and said, “Well, it doesn’t suck.”

The next day he came from three shots behind on the back nine to catch Ernie Els, winning with a 20-foot birdie putt on 18 and celebrating with a victory leap in which he barely got airborne. It didn’t matter: Two months short of 34, he was a major champion.

Sunday’s PGA victory was his sixth major — three Masters, two PGAs and a win at the 2013 British Open that was his most satisfying until he tapped in the last putt on Kiawah’s 18th hole Sunday to beat Brooks Koepka and Louis Oosthuizen by two shots.

It isn’t as if Mickelson hasn’t had setbacks. He had a complete mental meltdown on the 18th hole at Winged Foot when he had a chance to win the 2006 U.S. Open. “I’m just an idiot” was his comment afterward.

His Ryder Cup record — as with Woods — has been spotty at best, decidedly mediocre at worst. In 2014, he demeaned himself trying to blame captain Tom Watson after the U.S. team had been soundly beaten by Europe at Gleneagles.

He fired Butch Harmon as his coach in 2007 — another thing he shares in common with Woods — and split with Jim Mackay, his friend and caddie for 25 years, almost four years ago. He embarrassed himself again at the 2018 U.S. Open when he putted a ball that was still moving to let the world know that he believed the USGA had blown the Saturday golf course setup.

The most difficult time in his life, though, came when Amy was diagnosed with breast cancer in 2009. When he won the Masters a year later, his post-victory hug with her was one of golf’s more genuine and endearing moments.

The bottom line on Mickelson is this: He always comes back. He finds ways to get better. For years, he was a non-factor in the British Open because, as he readily admitted, he didn’t like being in Great Britain. “I don’t like the food, I don’t like the showers, I don’t like driving on the wrong side of the road,” he once said. “I come over here at the last possible minute and get out as soon as I can. Probably not the best way to win a golf tournament.”

For years, Mickelson would fly overnight Monday, practice Tuesday and Wednesday and then hope to have a chance beginning Thursday. When that didn’t work, he flipped 180 degrees: He started playing the Scottish Open the week before and brought his family with him to make that week a vacation.

In 2013, he won the Scottish and then, a week later, shot 66 the final day at Muirfield and won the British. He almost won it again three years later, playing brilliantly only to watch Henrik Stenson play a little more brilliantly. Mickelson shot a remarkable 65 on the final day, but Stenson shot 63 to win by three shots. Maybe the golf course was playing easy? Well, J.B. Holmes finished third, 11 shots behind Mickelson.

Mickelson is now looked up to by almost all of his fellow pros. “He’s like our papa bear,” Zach Johnson, a two-time major champion himself, said a couple of years ago. “We all admire him for what he’s done and for who he is.”

He still has one hole in his résumé: the U.S. Open. He has finished second six times. Before the PGA began, he accepted a special exemption from the U.S. Golf Association to play at Torrey Pines next month. The thought was he would play his last U.S. Open at the course where he grew up and where he won his first event as a pro more than 28 years ago.

But now he’s exempt for five more years. Is it likely that he’ll break through and win the U.S. Open four days after he turns 51? No. But was it likely he would ever win a major? Was it likely he would win in a country where he couldn’t stand the food or the showers? Was it likely he would hold off Koepka, a four-time major champion, on Sunday to add one more stunning moment to his golf legacy?

The lesson of this week: Don’t ever count out the great ones. Especially don’t count out a guy who signed all those autographs right-handed and played the game better than anyone has ever played it left-handed.

Lefty’s not done yet. And he may not be for a while.

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