(CNN)She was playing in her first major tournament and her first event outside of Japan, but Hinako Shibuno was unfazed as she clinched the AIG Women's British Open at Woburn Sunday.
Hinako Shibuno wins Women's British Open on debut
The 20-year-old fired five birdies on her back nine to hold off America's Lizette Salas by one shot.
Shibuno led by two strokes going into the final round but dropped back to the pack before pulling clear of Salas again and sinking a long birdie putt on the last to earn the $675,000 first prize.
World No.1 Ko Jin-young of South Korea was two shots adrift in third.
Shibuno, who was smiling and high-fiving fans throughout the final round, became only the second Japanese player -- male of female -- to win a major after Chako Higuchi at the 1977 Women's PGA Championship.
Asked how she will celebrate, she told reporters: "Eat a lot of sweets."
She added: "I do like typical Japanese sweets that's made of squid or seaweed."
Shibuno appeared so relaxed she was even joking with her caddie ahead of the crucial second shot into 18 with the tournament on the line.
"I was talking to the caddie over the second shot [saying] if I were to shank this, it would be very embarrassing," laughed Shibuno, whose manager Hiroshi Shigematsu can often be seen in amusing costumes to make her smile. On Sunday he wore a blue wig with a clown mask.
Shibuno was ranked 559th in the world at the beginning of 2019 but had climbed to 44th ahead of the event in Buckinghamshire, England following two wins on the LPGA of Japan Tour.
"Now that I've won, I think a lot of the Japanese people will know me, but in actuality, I just wanted to live a quiet life," she said.