Celine Boutier has birdied two of her last three holes to win the LPGA Tour event in New Jersey as two of the world's top three players faltered down the stretch.
Starting the final round of the Shoprite LPGA Classic five shots behind the co-leaders, Boutier ran off six birdies on the front nine of the windy Bayside Course at Seaview to join a growing list of contenders with an eight-under 63.
The 27-year-old from France holed a 12-foot birdie putt on No.16 and then birdied the par-5 18th from five feet to set the target at 14-under 199.
"I just made a lot of putts today and it wasn't the case yesterday," Boutier said.
"So I just feel like I honestly played really solid, gave myself a lot of opportunities, and dropped a lot putts, so that was definitely helpful."
Jin Young Ko and Inbee Park, who shared the lead going into the final round, couldn't match her.
Brooke Henderson of Canada birdied the 18th for a 64 to finish in a tie for second along with Park and Ko, who each closed with a 69, at 13-under.
Maria Fassi (64) was a shot further back in fifth with Patty Tavatanakit (69) three shots Boutier in sixth.
Victoria’s Su Oh carded a three-under 68 to get to 10-under, good enough for a share of seventh and her second top-10 of the year.
World No.2 Ko, going for her third win in her last five starts on the LPGA Tour, appeared to be in control until she started missing putts from the 10-foot range.
"I needed more birdies, but I couldn't," Ko said. "I needed a little more luck."
World No.3 Park rolled in a 20-foot birdie putt on the 14th to reach 13-under, and that’s where she finished along with Ko, who hit into a bunker and missed an eight-foot par putt on the 15th.
Boutier was on the practice green and then watching on TV in the clubhouse to see if her score would stand – and it did.
The Frenchwoman securing a first LPGA Tour win on American soil – her other title coming at the co-sanctioned 2019 Vic Open.
"It feels like my first win in Australia was so long ago," Boutier said. "I'm just over the moon."