Ko admits she will need something special on the final day to claim her third major win and says she is willing to be more aggressive to do so.
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.
"I always joked that a major would be my first win", Hall said.
Apart from her lone hiccup, Phatlum continued her relentless accuracy off the tee and into the green, carding a composed three-under-par 69 at Royal Lytham & St. Annes. Her last win was on the Asian Tour in January 2015 and she has only one top-10 finish all year.
Cheered on by a large gallery, Hall finished at 17-under 271, becoming the second English player to win the championship after Karen Stupples in 2004.
Hall finished up with her only bogey of the day on the eighteenth but never looked likely to allow her lead to slip and joined Dame Laura Davies, Allison Nicholls and Karen Stupples as an English-born victor of the British Open.
Phatlum, the third-round leader, came out strong with four birdies over the first six holes.
She tied for third at Kingsbarns previous year, and expects that she will be better for the experience. It was very close up to the last two holes and I holed all the putts'.
Hall took the outright lead for the first time in the tournament after a 20-foot putt for birdie at the 16th hole and went down the last with a three-shot lead after Pornanong, ranked No. 97 and also seeking her first major and LPGA title, missed a two-foot putt to make double-bogey at No. 17.More news: Kim K's gone and changed Chicago's name because it doesn't "flow"
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"I hit the ball really solid which was good after a pretty average ball striking day yesterday", she said.
Hall also wowed the fans at Centurion in May alongside Charley Hull, the pair reaching the quarter-finals of the GolfSixes and earning a 1-1 draw with their male English counterparts Eddie Pepperell and Matt Wallace.
Georgia Hall on Sunday became the fourth Englishwoman major champion when she carded a closing five-under-par 67 to clinch victory at the Women's British Open in Lancashire, England.
She got the final day off to a very strong start, scoring a birdie on the par-3 first hole to draw level with the Thai golfer.
"I got nervous too today so I just tried my best", said Phatlum, who sings songs in her head when she starts to feel pressure on the course.
Hall, who holed a string of great putts, had five birdies in a 69 to maintain high hopes of improving on last year's tie for third and become the first British victor since Scotland's Catriona Matthew triumphed at Lytham nine years ago.
★"I hope it will bring more sponsorship to the Ladies European Tour". I think the crowds love golf, they love seeing their LPGA players here.