A bogey-free final round followed by a playoff win over Lydia Ko handed Brooke Henderson the win at the Women’s PGA Championship on Sunday, the first LPGA major trophy for the 18-year-old Canadian.

In Sammamish, Washington, Henderson made history by becoming the youngest player to win the tournament. She also became the first Canadian to win an LPGA major since Sandra Post did it in 1968.

Incidentally, Post was also the youngest-ever winner at the time, and she too won her title in a playoff at the same tournament, then called the LPGA Championship.

Henderson’s second shot from the fairway in the playoff dropped well within her comfort zone for a birdie. Ko was first off the tee and the pressure was on the New Zealander to three putt her attempt. Once she missed, Henderson was clear to put away the contest and lift the Women’s PGA Championship trophy.

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It was Henderson’s second tour win, after taking the title at the Portland Classic last year with a dominant performance despite not yet being a full time tour player.

On Sunday, Henderson’s strong final round saw her stalking the world’s top ranked women’s golfer Ko on the scoreboard, whom she caught on the 17th with a long birdie putt that brought both players to six-under-par.

That score looked to be in danger at the final hole, however, when Henderson’s drive from the tee landed off the fairway, and her subsequent second shot from the trees hit some low-hanging branches to keep her 75 yards from the flag with two shots left on the par four finale. Under pressure, Henderson remarkably dropped her third shot on 18th within three metres of the hole, and then drained the par putt with ice-cold composure before heading to the clubhouse tied for the lead.

Nineteen-year-old Ko (who is about four and a half months older than Henderson and has been a tour regular since the age of 16), was playing behind her up-and-coming rival. She had a chance to take the lead on 17th, but where Henderson birdied on Sunday, the young Kiwi narrowly missed her second shot on the par three and settled to break even. She would miss another long birdie attempt on 18th sending her and Henderson to a playoff.

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While Ko and Henderson were fighting it out at the top, 20-year-old Ariya Jutanugarn of Thailand was charging ahead with two birdies on 16th and 17th to pull within one shot of the leaders. Her birdie attempt at 18th though missed to the left, forcing her to hold for third overall at five-under-par.

Brooke Henderson chips a shot at the Women's PGA Championship in Sammamish, Washington on June 9, 2016.

Brooke Henderson chips a shot at the Women’s PGA Championship in Sammamish, Washington on June 9, 2016.

Henderson – though in her first full year on the pro tour – has shown a remarkable knack for showing up and challenging at the majors.

It was in the Women’s PGA Championship a year ago that Henderson, then yet to be a fixture on tour, announced her arrival tying for fifth in Harrison, New York. She then tied for fifth again at the U.S. Women’s Open, the next major on the calendar.

At the first major of 2016, Henderson was 10th at the Dinah Shore.

Brooke Henderson tees off in the fourth round of the Women's PGA Championship on June 12, 2016.

Brooke Henderson tees off in the fourth round of the Women’s PGA Championship on June 12, 2016.

Coming into this weekend, Henderson got off to an electric start as the first round leader, helped by a hole-in-one that won her a car, which she gifted to her sister Brittany as part of a long-standing promise. The older Henderson has caddied for her younger sister in Sammamish and for much of this season helping to keep her lines straight.

Four-under-par (67) after the first round, Henderson’s next two days saw her shoot two over (73) on Friday and Saturday, respectively, to bring her even for the tournament, but with nobody running away with the contest, Henderson was well within striking distance on the final day.

The Canadian certainly saved the best for last with a six-under-par (65) finale, including an incredible eagle on 11th that put Ko on notice. For a change of pace, it was the world’s top player Ko – winner of the last two majors – who looked vulnerable as Henderson charged and eventually won her first career major.

With golf returning to the Olympic calendar this summer at Rio 2016 and the women’s game making its debut, Henderson is expected to challenge the world’s best for Team Canada.