The shaft of a golf club is about a half-inch in diameter, thicker than a pencil but slimmer than a broom handle. As a makeshift flagstick, for most golfers, it would be more suggestion than destination.

But Lydia Ko isn't most golfers. Five years ago, John Lister, a retired New Zealand tour professional, noticed Ko on the practice range at Gulf Harbour Country Club in Whangaparaoa, an Auckland suburb. She had stuck a golf shaft in the ground on one side of the range and was hitting wedge shots at it from the other, 80 yards away.

As Lister watched, Ko swung, beautifully smooth but with purpose. The golf ball rose, high but not too high, and struck its target. She hit another ball, and it also ended its journey by striking the distant shaft. As Lister continued to look on, Ko did it a third time.

"Three times in a row," Lister says. "It was just incredible, that ability to repeat, repeat, repeat. She makes it look so easy to do the same thing all the time."

Ko is tough and talented in dimensions that are hard to measure. No one wins an LPGA tournament at 15. No one becomes No. 1 in women's professional golf at 17. No one earns a seventh career LPGA victory days before turning 18.

Except Ko has done those things, to the astonishment of perhaps everyone except the people who knew Ko as she grew up in New Zealand. What she has achieved might be amazing, but it is no accident.

Lister was no stranger to Ko by the time he saw the accuracy hat trick. Before the girl turned 10, he had been a part of a regular Sunday game with her at Gulf Harbour for several years. The group was filled out by veteran Kiwi pro Bob McDonald and a talented Korean-born player 7 years older than Ko, Shin Ae "Sharon" Ahn, who took lessons from McDonald and was a friend of Ko's family. The foursome would play 15 to 20 times a year. Ko's mother, Tina Hyon, was always there and sometimes her father, Gil Hong Ko, was, too.

"Lydia's mum made sushi rolls for us to eat on the way 'round," Lister says. "I would talk to Lydia a lot. I liked her sense of humor and imagination. We had a lot of fun times."

"Big John," as Ko calls Lister, now 68, was a grandfatherly font of golf knowledge. He won once in America and regularly in his home country. He has been in the company of fine ball strikers. Lister did not meddle with Ko's technique, which had been capably handled by a young Auckland pro named Guy Wilson since she was in the first grade. His goals were to help Ko feel as comfortable on a golf course as in a playground swing and improve her course management.

From the first gentle tip Lister offered, Ko was a sponge for his advice. She had hit a drive down the middle of the fairway on a par 4 that she had no chance of reaching in regulation. She was going to hit her second shot down the center, too, until Lister asked her to pause. The hole was located on the back-left portion of the green behind a bunker. If the 8-year-old hit her second shot to the right side of the fairway instead of the center, Lister mentioned, her third would be easier. Ko played up the right.

"I didn't have to ever tell her again," Lister says. "She got it, understood completely. It was like she was born to play golf. She's once in a lifetime, really."

Now, everyone is watching

More than a decade has passed since Lister first became aware of Ko. She was 6, hitting balls off an artificial-turf mat in a bay at Takapuna, a busy double-decker driving range. As Ko followed through on her shots, her tiny body would be wrapped into a full finish, stretched like a taut rubber band. "She was a real little show-off," Lister remembers. "After a shot, she'd turn around and look down the range to see who was looking at her."

Rare is the golf fan who isn't looking at Ko now. Her quick ascendancy to the pinnacle of the women's game is unprecedented. No one in modern golf -- male or female -- has been so good so young as measured by victories at the highest level of competition. It is necessary to return to tournament golf's earliest days to find someone comparable: Tom Morris Jr., who won his first Open Championship in 1868 at age 17, and two more Opens as a teenager.

In 2012, Ko was 14 when she won the Women's NSW Open on the Australian Ladies Professional Tour. At the time, she was the youngest person to win a professional event. She won her first LPGA event at the record age of 15 years and 4 months at the 2012 Canadian Women's Open and captured five more LPGA titles before her 18th birthday on April 24 of this year. (Only Lexi Thompson, 16 when she won the 2011 Navistar LPGA Classic, has won an LPGA event while younger than 18.) The week Ko turned 18, during this year's Swinging Skirts LPGA Classic in San Francisco, she earned her seventh LPGA victory.

Heading into the second major championship of 2015, the Women's PGA Championship this week at Westchester Country Club in Harrison, New York, Ko has four chances left to make more history as the LPGA's youngest major winner. A victory by Ko at the Women's PGA, U.S. Women's Open, Women's British Open or Evian Championship would surpass Morgan Pressel, who was 18 years, 10 months and 9 days old at the 2007 Kraft Nabisco.

"You see such greatness, and you know it's a privilege to be able to watch it," Hall of Famer Amy Alcott says of Ko. "I was 18 when I joined the tour. I kind of get it. She doesn't really know how difficult this game, and life, can be yet. I think she has a very special gift, and I don't think there is any limit on it."

Ko now lives in Orlando, Florida, where you can find lots of professional golfers. Her coaches for the past 18 months, David Leadbetter and Sean Hogan, are there. The weather is good and so is the airport. "There are a lot of flights out of MCO," Ko says. "It's a really convenient place to be based."

Home -- where Ko developed into the person and golfer she is -- is 8,000 miles away. Ko moved to New Zealand at 6 and became a citizen when she was 12. "I loved growing up there," she says. "It is a very different culture from Korea. It is very relaxed."

Coach Guy Wilson and Lydia Ko clicked from the get-go and had a big-brother, little-sister-type relationship. Courtesy Guy Wilson

Learning and laughing

Wilson was 22, a fledgling professional at Pupuke Golf Club on Auckland's North Shore in 2003, when Tina came into the pro shop with Lydia. Lydia had received a 7-iron from her aunt and gone to a driving range in South Korea before the family moved to New Zealand.

The Ko family moved into a neighborhood close to Pupuke where many Koreans settled. "Tina wanted three lessons a week for Lydia," Wilson says. "I was just coming out of my apprenticeship and was only doing about five a week at that stage. I'm thinking, 'Hell, yeah, I'm happy to give three lessons.'"

Lydia was small and didn't know much English. Her early lessons with Wilson, who didn't speak Korean, weren't golf-intensive. "There is only so much you can do in a half hour to keep the concentration of a little girl who doesn't really understand what you're saying and can't hit it out of her shadow with equipment that was too big for her," Wilson says.

Wilson couldn't have been much more inexperienced when Lydia began taking lessons from him -- "Shoot, I didn't know; I was just taking a guess," he admits -- but just as she took naturally to the game, Wilson possessed what turned out to be a canny sense of how she could get better.

Guy Wilson kept things light to keep a young Lydia Ko interested. The formula worked. Getty Images

Lydia couldn't hit the ball more than 50 yards at first. Most of their time was spent on, or around, the green.

"Someone is not going to be able to double their distance in three or four months, although they definitely might be able to chip it twice as close," Wilson says. Ko practiced her short game extensively, and it is among the best on tour. "That's probably the majority reason she's so good around the greens now," Wilson says. "She's got the instinct of a 40- or 50-year-old the way she sees things."

When they worked on Lydia's long game, Wilson -- in contrast to a popular teaching philosophy that says junior golfers should learn to hit the ball hard, then learn to control it -- discouraged her from "trying to create more power than she could." Influenced by physiotherapists at the Institute of Golf that he co-founded after leaving Pupuke, Wilson believed such an approach would have wrecked her swing and eventually her body.

"If our goal from day one was to get her to hit it as far as she can, she wouldn't be playing golf anymore," he says. "She'd be busted, her back would be done. We always said that rhythm was good."

So was a laugh. Wilson kept things light to keep Lydia interested. It is impossible to pinpoint exactly why certain people click, but Wilson and Ko did.

"He had a great attitude and they had a wonderful big-brother, little-sister-type relationship," says Sandie Jennins, an eight-time club champion at Pupuke and a mainstay in women's golf around Auckland. "The banter between them was always there."

A diverse golf education helped steel Lydia Ko for a pressure-packed amateur showdown with Cecilia Cho. Courtesy The New Zealand Herald/Babiche Martens

Decision-making, not just ballstriking

Amid the teasing, particularly as she got older, Ko's golf hours were very focused. "One of the critical things was how smart she worked," says Gregg Thorpe, high performance manager for New Zealand Golf, the country's governing body. "Guy and her dad were very good at getting the most out of her time. It was never about hitting ball after ball. It was about challenging her and her decision-making and playing the game, not just ingraining techniques."

With Wilson lobbying for her, Ko got a $100 annual junior membership at Pupuke when she was 7. Although it didn't have an extensive practice ground, the course encouraged diverse shot-making because of its terrain. "It's carved around the side of a hill," says the club's general manager, Laurie Flynn. "You're playing shots with the ball below you or above you, all sorts of uneven lies."

Ko's golf education became diverse. The many weekend rounds with Lister and McDonald, men who had the wisdom that comes only from being around the game for decades, accelerated Ko's ability to play the game rather than be a robotic ball-beater. The old pros used the soft sell, sprinkling suggestions when they would be most effective.

"We might go six or seven holes and not say a word," McDonald says. "Then we'd go, 'What are you doing here?' Or wait until the end of the round and bring it up."

When Ko grew a bit older, those valuable Sunday sessions gave way to formal training with someone else, mental performance coach David Niethe. Ko saw Niethe -- who has degrees in neurolinguistic programming and hypnotherapy and consults with athletes in various sports -- for an hour once a month for approximately seven years.

As Lydia Ko's mental performance coach, David Niethe stressed equanimity, and that sure is apparent today. Courtesy David Niethe

"Lydia has been hypnotized many a time by me," says Niethe, 46, a large brick of a person who used to compete in strong-man competitions. In using hypnosis during her formative years as a golfer, Ko has that in common with Tiger Woods, who as a teenager was hypnotized by Dr. Jay Brunza, a friend of his late father, Earl, as one tool to better his play.

"We would use hypnosis if we deemed we needed to," Niethe says. "There was a lot of action, reflection, deciding strategies. We'd talk about something, then try to make it a habit."

As Ko has risen to No. 1 in the world, casual fans to champion golfers have noticed how placid and even-keeled she is. When Hall of Famer Pat Bradley competed, her intensity warmed a day by five degrees. "My family was a bundle of nerves when they watched me play," Bradley says. In Ko's gallery this year at the Founders Cup, Bradley couldn't believe the vibe. "You watch Lydia, and she is so cool, calm and collected, and she expresses it to everybody who watches her. And you feel that same calm, cool collectiveness."

That remarkable demeanor is at least in part a result of the coaching Ko received from Niethe, who stressed equanimity.

"You never see Lydia upset, nor do you see her overly excited," he says. "What we've taught her over the years is what we call 'the performance window.' She doesn't get too passive. She doesn't get too aggressive. She just stays assertive. And that's the key."

Despite all the skill Wilson had seen from Ko up to then, her performance in the 2009 New Zealand Women's Amateur, when she was 11, raised his appreciation to a level that convinced him great heights were possible. Ko advanced to the final against 13-year-old Cecilia Cho, a rival who was the No. 1 amateur in the world and, like Ahn, a strong source of motivation.

The Ko-Cho showdown captivated Kiwi golf and attracted a horde of media attention, including photographers and videographers who did not understand customary coverage rules. Ko lost to Cho, 4 and 3, but her composure never wavered despite the stakes and the stress.

"People can get uptight for a bloody two-dollar haggle," Wilson says. "But that day, playing for a national title at 11, cameras a few feet from her club on the backswing, Lydia didn't care. She'd hit so many golf balls that's she'd just press go."

Lydia Ko's mom and dad have been described as devoted but not overbearing like some golf parents. Copyright USGA/Steve Gibbons

Blessed with sound parenting

Before the 2012 New Zealand Women's Open, a Kiwi television magazine show, "Close Up," broadcast a feature on Ko and Wilson. "My life seems to be golf, golf, golf, golf, golf," Ko told correspondent Abby Scott. "I miss, like, seeing my friends going to the movies. Last year, oh my god, I still want to see my friends. But my parents kept telling me if you make a sacrifice, something that you want to achieve will come."

Beyond her natural talent enhanced by instruction, Ko certainly put in the time. Wilson and Niethe believe in a theory published by Swedish psychologist K. Anders Ericsson in a 1993 study and popularized by Malcolm Gladwell's 2008 book "Outliers: The Story of Success" that 10,000 hours of "deliberate practice" is the key to world-class excellence.

Whether it was the evenings after dinner at the Takapuna range -- where she would try to keep up with Ahn in the adjacent hitting bay -- skipping down the sloping fairways of Pupuke or locking up after a late session with the key she was given at the Institute of Golf, many in greater Auckland observed how much Ko put into golf.

Sara Jasmat, a Pilates instructor and low-handicap amateur, recalls a day she and her husband played 36 holes at North Shore Golf Club. Ko was practicing when Jasmat teed off and when she came by the clubhouse after nine, 18 and 27 holes. When Jasmat putted out on her 36th hole, Ko was still there.

"She was there the whole day," Jasmat says. "At the end she was playing in the dark, and her dad had his night-vision binoculars on so he could see where the balls were going."

In the 10,000-hour vein, Lydia Ko put her time in, often into the dark. Martin Hunter/Getty Images

Despite their deep involvement in their younger daughter's development and the extreme amount of time she devoted to the sport, Ko's parents won over those in the New Zealand golf community for their sound parenting. Their style stood out from the overbearing attitude sometimes seen from Korean parents of junior golfers who could carry their boot-camp approach too far.

"I've experienced it," says Jennins. "I had one girl on a team, if she lost a match they would physically abuse her. We've had a few of those instances. Lydia's dad has broken that pattern. Gil Hong and Tina are lovely parents."

To Niethe, Ko is an appealing and effective blend of her parents' personalities. "What you have is a very strong, articulate, intelligent side with Mum and a fun-loving, extroverted character with Dad."

There is a Korean proverb that says, "You will hate a beautiful song if you sing it too often." Jenna Hunter, a 26-year-old aspiring New Zealand professional, played on the North Harbour district golf squad with Ko when Ko was 10, much younger than most of her seven teammates. Hunter used to wonder about Ko's motivation, if all the golf was her idea.

"Her parents were almost always around, but on a trip I'd be a bit of a mother figure," Hunter says. "When I'd have a moment alone with her, I asked if she loved golf. She always said, 'Yes, I love it.'"

Niethe describes Ko's affection for golf another way. "As we mature through life, it's like the creative side gets beaten out of us as we go into the daily grind," he says. "Most of us as kids know what it's like on Christmas Eve. You didn't know what you were going to get, but you knew Santa was coming and it was pretty exciting. That's sort of the attitude Lydia brings to golf -- what wonderful thing am I going to do today, what am I going to create today?"

Lydia Ko would like to be known as not simply a great player, but a nice person, too. Andrew Redington/Getty Images

A tiger with a smile

When McDonald watches Ko, he thinks about legendary Australian golfers Peter Thomson and Kel Nagle. "They went around the course with a smile on their face like it was a Sunday stroll," McDonald says. "They just got on with it. She reminds me so much of those guys. She just gets on with it. "

Ko's shot-making, rooted in the formative days when Wilson stressed control, is also old-school. In contrast with some of her young peers on the LPGA who swing aggressively at their iron shots, there is an efficient daintiness to Ko's approach shots, on many of which she grips down on the handle. "I hit a lot of three-quarter shots. It's what I've always done," Ko says. "For me to hit a fuller shot with an iron feels kind of awkward."

She has been eligible to vote and have a drink in New Zealand for less than three months yet possesses a game that has past and present stars in awe.

"As young as she is, to be doing what she's doing, there is no other word but incredible," says two-time LPGA major champion Brittany Lincicome. "When I was her age, I was trying to figure out what I wanted to do with my life, whether I could make it out on tour."

Ko has played in 53 LPGA events as an amateur or pro and hasn't missed a cut. She had 29 consecutive rounds under par, tying Annika Sorenstam's LPGA record. In addition to her seven LPGA victories, she has 22 top-10 finishes.