A disastrous final round three-over-par 75 cruelled Australian Minjee Lee's chances of a first major title as Georgia Hall broke her maiden duck on Tour with victory at the Women's British Open.
She stamped her authority with three birdies in a four-hole stretch to beat Thailand's Phatlum by two strokes at Royal Lytham & St. Annes.
She followed Stupples and Catriona Matthew - in 2009 at Lytham - as the only British winners of the Women's British Open since it achieved major status in 2001.
After a solid first half of the year as an LPGA member, Hall earned her first top-10 finish at the Thornberry Creek LPGA Classic last month, and she has now produced the finest performance of her career to win her maiden major title. "It was my goal when I was 9 to win the British Open".
"I'm glad I finally played well around here, just in time for it to leave", Thomas said. I just had to stay calm.
Hall added: "I was in the final round a year ago [at Kingsbarns] and that is definitely going to help me".
Pornanong began the day with a one-shot lead over Hall and four birdies from her first six holes doubled her advantage. She joins a list of players who have gone on to dominate in the women's game: Michelle Wie (2005), Anna Nordqvist (2008), Danielle Kang (2011), Lydia Ko (2012), and Georgia Hall (2013).
Hall also fought back tears at the presentation ceremony as she dedicated the victory to her grandfather, saying: "There's someone very special at home that's going through a bad time so this is for you Grandad".
Hull tapped in for a bogey - her first of the day - at the last hole to clinch a two-shot victory over Pornanong.
"I don't think it's all sunk in for me".
Georgia Kelly Hall was born in Bournemouth on April 12, 1996, two days before Sir Nick Faldo pulled off one of the greatest sporting comebacks in history to win his third Masters title over a luckless Greg Norman at Augusta National.
The resulting bogey saw the 28-year-old's lead cut to a single shot and Hall kept it that way thanks to a superb par save on the ninth after finding a greenside bunker with her tee shot.
Hall was not at her best on Saturday.
Hall nailed a 20-foot eagle putt on the final hole to spark wild celebrations, and they went on to humiliate South Africa's George Coetzee and Haydn Porteous 4-1. Two-over after four holes, she then hit a purple patch with birdies at five out of six holes from the fifth.
Hall played safe in three-putting from distance in front of Royal Lytham's storied clubhouse and celebrated her first win on the LPGA Tour. "I felt like I putted my par putts really well, but the birdies putts weren't dropping that much, but to have a bogey free round especially at a major, I will definitely take it, so hopefully I have a lower one tomorrow".