Lytham St Annes - England's Georgia Hall showed grit and a steely nerve to win the Women's British Open with a superb final round of five under par 67 at Royal Lytham and St Annes on Sunday. 

With her father Wayne acting as her caddie, the 22-year-old came from a shot behind overnight leader Thailand's Pornanong Phatlum to post a 17 under par total and claim a first major title and the $490 000 winner's cheque. 

Over the 72 holes, Hall made only three bogeys - she could well afford the one at the last - and her six-birdie final round secured a two-shot victory over Pornanong. 

Hall, whose first name is in honour of the American state that hosts the Masters at Augusta, had only won twice previously since turning professional in 2014, as a rookie on the Ladies European Tour Access Series and at the 2016 Victorian Open in Australia. 

The final day turned out to be a two horse race between the pair at the back of the field, Hall and Pornanong. 

The Thai 28-year-old was two ahead after four birdies in the first six holes and still one ahead at the turn. 

But Hall staged a great back nine charge with three birdies in four holes from the 13th, the 25-footer at the 16th earning the lead for the first time. 

Hall is the first British winner since Scotland's Catriona Matthew, also at Lytham in 2009, and joins Laura Davies, who has four, Alison Nicholas (1997 US Women's Open) and Karen Stupples (2004 British Open) as English winners of a women's major. 

Pornanong, leader at halfway and after 54 holes, did little wrong, but was finally overtaken by Hall's late great run and only then started making costly errors. 

A double-bogey at the 17th finally ended her challenge. 

Pornanong closed with a 70 for 15 under par with South Korea's Ryu So-yeon in third place on 13 under after a 70 that was blighted by a triple-bogey seven at the third. 

Hall, joint third at The Open in Kingsbarns in Scotland last year, was able to enjoy the walk down the 18th - by then she had a three-shot lead and she played for a safe bogey. 

Atthaya Thitikul was the only amateur to make the cut, and her reward was to win the Smyth Salver. 

The Thai 15-year-old closed with 77 for 12 over par.

Leading final round scores from the women's British Open at Royal Lytham and St Annes on Sunday (GBR & IRL unless stated - par 72):

271 - Georgia Hall 67-68-69-67 

273 - Pornanong Phatlum (THA) 67-67-69-70

275 - Ryu So-yeon (KOR) 69-69-67-70 

279 - Kim Sei-young (KOR) 71-71-71-66, Ariya Jutanugarn (THA) 71-70-69-69, Mamiko Higa (JPN) 66-69-71-73

280 - Feng Shanshan (CHN) 71-71-69-69, Carlota Ciganda (ESP) 69-73-68-70, Liu Yu (CHN) 69-72-68-71

281 - Minjee Lee (AUS) 65-70-71-75

282 - Thidapa Suwannapura (THA) 72-71-67-72, Lee Jeong-eun (KOR) 73-70-71-68, Lydia Ko (NZL) 68-71- 70-73, Brooke Henderson (CAN) 69-70-69-74

283 - Jaye Marie Green (USA) 74-69-73-67, Su Oh (AUS) 73-70-72-68, Brittany Altomare (USA) 70-70-70-73, Teresa Lu (TPE) 67-69-73-74, Park Sung-hyun (KOR) 67-70-69-77

284 - Madelene Sagstrom (SWE) 69-70-74-71, Kang Haeji (KOR) 72-72-70-70 

285 - Sandra Gal (GER) 68-74-72-71, Ryan O'Toole (USA) 72-71-72-70, Aditi Ashok (IND) 72-72-73-68, Kim Hyo-joo (KOR) 72-69-72-72, Pannarat Thanapolboonyaras (THA) 73-71-69-72, Phoebe Yao (TPE) 71-71-67-76