Kang, a two-time US Women’s Amateur champion, held off a charging Brooke Henderson, the Canadian teenager electric over the closing stages as she desperately tried to defend the title she won in a play-off over Lydia Ko last year.
Long considered an underachiever in the professional game after a glittering amateur career, Kang was sublime Sunday as she grabbed the tournament by the scruff of the neck.
Aggressive all day, the 24-year-old said self-belief was the key ingredient to a remarkable breakthrough victory.
“I just trusted in my game and I didn’t worry about anything else,” she said moments after the final putt dropped.
“It’s all about believing in yourself and just being confident and that’s what I did.”
Kang began the day tied for the lead with Chella Choi and looked to be running away with the tournament midway through the back nine when she built a three-shot lead.
A bogey at the 10th lit a fire under the confident American who immediately reeled off four straight birdies to stamp her authority on the leaderboard.
Even a heavy-handed chip after missing the 16th green presented no problem, Kang holing her par putt from almost 20 feet to maintain momentum.
But she needed to be on top of her game as Henderson continued to apply pressure and, despite missing several makeable birdie chances, the 19-year-old struck at the treacherous par-3 17th with a brilliant birdie to reduce the margin to two.
Kang hit one of her few poor shots all day at the long par-3 just moments later and when she failed to get up and down the lead was one and Henderson appeared to have the ascendancy.
As Kang stood on the 18th tee, Henderson, playing in the group ahead, rolled her eagle attempt at the par-5 within an inch of the hole and drew a huge roar from the gallery.
Standing over her ball on the tee as the cheers erupted, Kang backed off her shot and gave a wry smile as she got set again, this time a co-leader with one hole to play.
It was testament to her ball-striking and mental fortitude that she hit two of her best shots of the day, splitting the fairway from the tee and rifling a fairway wood to the heart of the green at the par-5 finishing hole.
Her approach putt from some 30 feet came up two feet shy but the result was never in doubt as she calmly brushed in the birdie to take the tournament by a shot.
For the second year in a row, the revitalised Women's PGA provided a thrilling Sunday finish in a tournament that is going from strength to strength.
NEWLY CROWNED MAJOR WINNER DANIELLE KANG WITH SOME TIPS TO IMPROVE YOUR DRIVING:
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