Ranked 114th in the world and direct from a missed cut last week, young Australian Hannah Green led wire-to-wire Thursday to Sunday at the KPMG Women’s PGA Championship and clinched her first LPGA Tour victory and first major championship with a pressure-packed par putt on the 72nd and final hole at Hazeltine National Golf Club.

Aussie, Aussie, Aussie, explain that one.

“I have no idea,” she said after fellow countrywomen and men doused her with Budweiser in celebration on the 18th green. “I just can’t believe I’m here right now.”

Mentor, benefactor and now fellow Australian major champion Karrie Webb counseled and cooked ribs on the barbie for her Saturday night. Then Green went out Sunday and defeated defending champion Sung Hyun Park by a single shot after her final-round lead fluctuated from one shot to four shots and back to one.

VideoVideo (01:18): Hannah Green talks with the media following her victory Sunday at Hazeltine.

Two-time major winner Ariya Jutanugarn plummeted from one shot off Saturday’s lead with a Sunday 77. Englishwoman Mel Reid’s 66 from earlier in the day left her three shots back and tied with Nelly Korda for third.

Only 22, Green ultimately won when she got up and down from a greenside bunker at Hazeltine’s long, uphill closing hole, making a 5½-foot putt that dropped without a doubt.

Webb called the par save “world class,” adding: “Put the best women or male players in the world under that situation and how many of them would get it up and down?”

Park, the world’s fourth-ranked player, shot 70, 71, 71 and 68 in the championship and still couldn’t catch the woman whose only three pro victories were on the LPGA’s developmental tour two years ago. Park couldn’t catch up even after she made a long birdie putt on No. 18 in the pairing ahead of Green to ratchet up the pressure another notch.

Green’s four-shot lead Sunday dwindled when she bogeyed three of four holes midway through her round. But she persevered when it mattered most: She hit the fairway through a breeze on a demanding drive at the par-4 16th hole along Hazeltine Lake and made a 20-foot birdie putt to reach 9 under for the championship. She stayed there after she hit the 18th fairway, too, and still made par after the first 4-iron she hit all day came up well short in the left greenside bunker.

“That was the most nervous I was all day,” Green said.

She had talked with her caddie during a wait at the 18th tee about future Women’s British Open venues, which helped calm her nerves. A little.

“I just wanted to talk about anything besides what was really happening at the moment,” said Green, the only child of a Scottish mother and a New Zealander father. “I don’t think I’ve ever had my heart race so fast.”

Every major championship won is defined by a singular moment or two, as Webb well knows after winning 41 times (including seven majors) on tour. She deemed Green’s birdie at dangerous No. 16 as that moment.

Ranked 60th in fairways hit among the 80 players who made Friday’s cut, Green drove assuredly into the fairway on a hole that played 375 yards after championship officials shortened it to a tantalizing 245 yards Saturday.

On Sunday, Green took Hazeltine Lake — which runs the length of No. 16’s right side — out of play with two rock-solid shots and one putt that were unmoved by a gusty wind off the lake.

“I’m glad they put the tee back,” Webb said. “The winner needs to stand up there — that’s probably one of the hardest tee shots on the golf course — and hit that shot.”

In 2007, Webb started a series of youth tournaments in Australia that awarded the season’s two winners a $10,000 scholarship for travel expenses and the opportunity to experience a major championship in America by staying with Webb for the week.

The first season’s winner stayed with her at the 2008 U.S. Women’s Open, which happened to be held at Interlachen Country Club in Edina. Green won a scholarship two consecutive years, starting in 2015. This year’s recipients wrapped themselves in Australian flags and colors and wore tutus while cheering on Green all week.

Webb revealed she said little before Sunday’s final round to Green, who quietly cooked herself some eggs after sleeping on a lead for a third consecutive night.

“We had a huge storm last night and there was a crack of thunder that shook the house,” Webb said. “I asked her if she heard it. She didn’t. I said, ‘She’s fine today.’ ”

The only substantial chat Webb said they had was Saturday, after Webb noticed how Green talked about the element of luck in her postround media interviews.

“I just wanted to tell her that, you know, lucky breaks happen to people that win,” Webb said. “That always happens the weeks that you win.”

Green left Hazeltine on Sunday evening with a big silver trophy, a check for $577,500 coming and a handwritten poem written for her by 7-year-old Lily Kostner, a soccer player and second-year golfer from Minneapolis. Green had handed her a golf ball and high-fived her at the ANA Inspiration major in Rancho Mirage, Calif., in April.

The poem included this line at the bottom: You Can Win This.

Green stuck the poem in the back of her yardage book — “I didn’t want it to get wet and ruined” — and tucked it into her back pocket.

“A couple times on the back nine, when I was feeling nervous and had some time, I actually read it to myself,” she said. “I have to thank Lily for writing that. I think it really helped me.”