Park - a former World No. 1 - claimed the trophy by a single shot in a tournament cut to 36 holes when the bulk of the opening two rounds were lost to bad weather.
With the field unable to begin the opening round until 3.30pm Friday it was a disjointed and confusing event with Park finishing several holes ahead of second-placed Lindy Duncan and on the opposite side of the Old American Golf Club layout.
Duncan, who hit off the 10th tee, made a costly bogey at her 15th hole of the day when a short par putt caught the lip and spun out.
The American hit back with three brilliant birdies in a row to close but with Park holing from off the green at the 18th at around the same time to get to 11-under, it was too little too late.
Oh. What. A. Shot.
Sung Hyun Park puts an exclamation point on her final round as she chips-in for birdie on 18 to finish at 11-under @VOATexasLPGA.May 6, 2018
Lydia Ko finished the best of the Australasian contingent, her two-round total of 6-under good for a share of eighth place.
Minjee Lee was T19 at 4-under for the week, one ahead of Katherine Kirk who finished T23.
Su Oh, who again started brilliantly with a 3-under 68, faded in the second round to drop to 2-under for the week and a T32 finish, one ahead of Hannah Green whose T46 at 1-under was matched by Karrie Webb.
Both Sarah Jane Smith and Rebecca Artis finished over par and outside the cut off for payment which was instituted instead of a cut.
Park was ecstatic with the victory and particularly the circumstances of her final hole after a season where she has struggled around the greens.
“I knew it was a pretty important shot,” she said of what was ultimately pivotal for the win.
“It was a difficult shot and I’m glad I made it. I know my stats are a little bit off in my short game, but I’ve been working hard and it paid off today.”
Watch ==> pic.twitter.com/hJMgUyYi07— LPGA (@LPGA) May 6, 2018
For runner-up Duncan the disappointment of the short par miss at a crucial moment spurred her on to a spectacular finish.
“I missed a short one [on No. 6] and I said to my caddie, Kyle, ‘What do we need to do,’ and he said, ‘Let’s go birdie, birdie, birdie,’” Duncan said after the round.
“It was a crazy week but is was a good tournament. I think I’m trending in the right direction.”
China’s Lu Yiu finished third outright while Ariya Jutanugarn and Sei Yong Kim shared fourth. Impressive young Indian player Aditi Ashok set the clubhouse target at 7-under early in the day and eventually shared sixth place alongside Jenny Shin.
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