PORTLAND, Ore. -- Teenager Chanettee Wannasaen played a five-hole stretch in 6 under early in the final round Sunday and closed with a near-flawless 9-under 63 for a four-stroke victory at the Portland Classic to become the first Monday qualifier to win on the LPGA Tour since 2015.
Wannasaen arrived at Portland ranked 367th and having missed nine straight cuts in her rookie season. The 19-year-old from Thailand credited her caddie for keeping her calm and put together four stellar rounds in the 60s at Columbia Edgewater. She shattered the tournament scoring record by five strokes with a 26-under 262 total for her first LPGA Tour victory.
"I don't give up. Yeah, I don't give up," Wannasaen said.
Wannasaen is just the third qualifier to win on tour. Canada's Brooke Henderson was the last Monday qualifier to win, taking the same Portland event in 2015. The other qualifier to finish first was American Laurel Kean, who claimed the State Farm Classic in 2000.
Third-round leader Megan Khang failed in her bid to win consecutive events. The 25-year-old American, a winner a week ago the CPKC Women's Open at Shaughnessy in Vancouver, British Columbia -- her first on tour -- closed with a 1-under 71 and finished alone in sixth place at 19 under.
Khang was satisfied with her performance over the last two tiring weeks.
"You know, game is pretty solid," she said after a round that included three birdies and two bogeys on the back nine. "I mean, I can't really say too much about today. A couple putts didn't drop, but overall, I mean, Chanettee played amazing. ... You're out there and there is nothing you can do about that. Gave myself a bunch of chances ... again, putts didn't drop."
Wannasaen, who had previously won on the Access Series of the Ladies European Tour and Thai LPGA, lost a playoff to Yue Ren last week in Idaho in the Epson Tour's Circling Raven Championship. She admitted the extended run of missed cuts weighed on her, but she credited the Epson Tour with boosting her confidence.
Xiyu Lin of China closed with a 64 for a 22-under 266 total and was second. China's Ruoning Yin (64), American Gina Kim (66) and Spain's Carlota Ciganda (67) tied for third another stroke back..
Tied for second place entering the round, Wannasaen charged into the lead with birdies at Nos. 3 and 5, an eagle at the par-5 fifth, and two more birdies at the sixth and seventh holes -- a stretch of 6 under that catapulted her into the lead at 23 under.
She carded a 30 on the front nine and was never really pressured on the inward nine, methodically playing the back and adding three more birdies to her total. She increased her advantage with consecutive birdies at Nos. 13 and 14, and she added another at the 17th to increase her lead to five stokes with four to play.
"I really like this course because I can make a lot of birdies, and I think the course is really beautiful," Wannasaen said.
One of few hiccups in her final round came at the 72nd hole when Wannasaen, who hit 13 of 14 fairways, powered her approach long and over the green -- one of three missed greens in regulation in the final round. She chipped short but punctuated her bogey-free round and victory with a 10-foot par putt.
Lin, who changed her putting grip this week, feverishly tried to rally from an opening 71 that included two bogeys and a double-bogey. But she just wasn't able to complete her comeback.
The Associated Press contributed to this report.