Phil Mickelson holds the Wanamaker Trophy after winning the PGA Championship golf tournament on the Ocean Course, Sunday, May 23, 2021, in Kiawah Island, S.C. (AP Photo/David J. Phillip)

KIAWAH ISLAND, S.C. — The pandemonium closed in around Phil Mickelson as he walked toward the 18th green of the Ocean Course at Kiawah Island, where thousands upon thousands of euphoric fans wanted a piece of the history he delivered Sunday in the PGA Championship.

For all the thrills and spills that have defined Mickelson's 30 years of pure theater, the left-hander's latest act gave him his own place in the game: A major champion at age 50, the oldest in the 161 years of major championship golf.

That final walk toward a two-shot victory was as much stress as he faced over the final hour, and it was a bit scary until Mickelson emerged out of the masses and flashed a thumbs-up.

"Slightly unnerving," Mickelson said of the gallery's pursuit, "but exceptionally awesome."

Just like Lefty's game.

Mickelson, who will turn 51 on June 16, never thought he was too old to win again on the PGA Tour, not even at a major. He just didn't have much evidence on his side until a remarkable four days at Kiawah Island, where he kept his nerve and delivered all the right shots for his sixth major championship — and by far the most surprising.

He made two early birdies with that magical wedge game that never left him, then let a cast of challengers fall too far behind to catching him in the shifting wind off the Atlantic.

Mickelson closed with a 1-over-par 73 to finish at 6-under 282, adding to a major haul that already included a trio of Masters victories (2004, 2006, 2010), the 2005 PGA Championship and the 2013 British Open. Second place on this day was shared by four-time major champion Brooks Koepka (74) and South Africa's Louis Oosthuizen (73), the 2010 British Open winner.

"One of the moments I'll cherish my entire life," Mickelson said. "I don't know how to describe the feeling of excitement and fulfillment and accomplishment to do something of this magnitude when very few people thought that I could."

That list didn't include Mickelson.

Never mind that he had not won in more than two years on the PGA Tour — he did win his first two starts as a senior golfer on the PGA Tour Champions last year — where he had not registered a top-20 result in nearly nine months. Top-21 finishes at the Masters last month and in 2019 were his best showings at the majors since a runner-up finish at the 2016 British Open. He was No. 115 in the Official World Golf Ranking.

"This is just an incredible feeling because I believed it was possible, but everything was saying it wasn't," Mickelson said.

Julius Boros for 53 years held the distinction of golf's oldest major champion. He was 48 when he won the 1968 PGA Championship.

The record now belongs to Mickelson, the Californian whose legacy is as much rooted in longevity as any of the skills that have made him among the most exciting players in the game.

Mickelson became the 10th player to win majors in three decades, an elite list that starts with Harry Vardon and was most recently achieved by Tiger Woods, whose 15 major titles trail only all-time leader Jack Nicklaus (18). Woods, who won the Masters in 2019 at age 43 after four back surgeries, was among those who sent a tweet of congratulations.

Three months after 43-year-old Tom Brady won a seventh Super Bowl championship, Mickelson added to this year of ageless wonders.

Mickelson became the first player in PGA Tour history to win tournaments 30 years apart. The first of his 45 titles was in 1991, when he was still a junior at Arizona State.

"He's been on tour as long as I've been alive," said Jon Rahm, the 26-year-old Spaniard with five career PGA Tour victories. "For him to keep that willingness to play and compete and practice, it's truly admirable."

Koepka and Oosthuizen had their chances Sunday, but only briefly. Koepka was 4 over on the three par 5s he faced when the game was still on. Oosthuizen hit into the water as he was trying to make a final run.

"Phil played great," Koepka said. "It's pretty cool to see, but a bit disappointed in myself."

Koepka also got lost in the chaos of the crowd at the end and said it was the most his right knee, on which he had ligament surgery two months ago, hurt all day.

This was history in the making. No one wanted to miss it.

Tom Watson came close in the 2009 British Open when at 59 he had a one-shot lead playing the 18th hole and made a bogey, then lost a playoff to Stewart Cink. Greg Norman was 53 when he had the 54-hole lead but failed to hang on in the 2008 British Open.

Mickelson didn't let this chance pass him by.

"It was like the Phil that I remember watching just when I turned pro, and it was great to see," Oosthuizen said. "I mean, what an achievement to win a major at 50 years old, and he deserves all of that today."

Baylor School graduate Harris English (72) tied for 64th at 8 over.

Mickelson's victory came one week after he accepted a special exemption into the U.S. Open because, at No. 115 in the world and winless the last two years, he no longer was exempt from qualifying for the one major that has eluded him. As recently as a month ago, he was concerned he could not keep his focus for 18 holes and kept throwing away shots that set him back.

And then he beat the strongest field of the year — 99 of the top 100 players — and made it look easy at times.

The PGA Championship had the largest and loudest crowd since professional golf's return from the COVID-19 pandemic — the PGA of America said it limited tickets to 10,000, and it seemed like twice that many — and it was clear what they wanted to see.

The opening hour made it seem as though the final round could belong to anyone. The wind finished its switch to the opposite direction from the opening rounds, and while there was low scoring early, Mickelson and Koepka traded brilliance and blunder.

Koepka flew the green with a wedge on the par-5 second hole, could only chip it about six feet to get out of an impossible lie and made double bogey, a three-shot swing when Mickelson hit a deft pitch from thick grass behind the green.

Mickelson holed a sand shot from short of the green on the par-5 third, only for Koepka to tie for the lead with a two-shot swing on the sixth hole when he made birdie and Mickelson missed the green well to the right.

Kevin Streelman briefly had a share of the lead. Oosthuizen was lurking, even though it took him seven holes to make a birdie. And then the potential for any drama was sucked out to sea.

Oosthuizen, coming off a birdie to get within three, had to lay up out of the thick grass on the 13th and then sent his third shot right of the flag and into the water, making a triple bogey.

Just like that, Mickelson was up by five and headed toward the inward holes, the wind at his back on the way home with what seemed like the entire state of South Carolina at his side.

The next major stop is the U.S. Open at Torrey Pines Golf Course in San Diego, where Mickelson will try to complete the career Grand Slam in his hometown.

"It's very possible that this is the last tournament I ever win, if I'm being realistic," Mickelson said. "But it's also very possible that I may have had a little bit of a breakthrough in some of my focus, and maybe I go on a little bit of a run. I don't know.

"But the point is that there's no reason why I or anybody else can't do it at a later age. It just takes a little bit more work."

Even at 50, Mickelson still keeps everyone guessing what he will do next.


Former CCS golfer on Korn Ferry Tour

Former Chattanooga Christian School golfer Scott Stevens tied for 26th Sunday in the Korn Ferry Tour's AdventHealth Championship in Kansas City, Missouri.

Stevens closed with a 4-under-par 68 to finish at 9-under 279 at Blue Hills Country Club. Cameron Young also shot a 68 to seal a wire-to-wire victory as he finished at 17 under, two shots ahead of South Africa's Dawie van der Walt (68).

Stevens, 24, was making his third start on the Korn Ferry Tour, having tied for 17th a week earlier at the Knoxville Open after missing the cut at the Huntsville Championship at the start of the month.