Taiwan's Yani Tseng held off a late challenge from Katherine Hull to clinch the British Women's Open by one shot at Royal Birkdale.

Tseng, 21, who led the tournament since Thursday evening, when she shared the top of the leaderboard with the Australian Hull, had been four shots clear at the start of the day. But bogeys at the 3rd, 8th and 10th holes allowed Hull the chance to hit back. Two birdies on the back nine closed the deficit to one stroke but Hull's hopes of forcing a play-off ended following a poor third shot on the 18th.

After just missing a birdie when a 20-foot putt lipped out on the par-five 17th, Hull was given further encouragement when Tseng's tee shot at the 18th found the sand. Tseng opted for safety while Hull attacked the green but the Australian overhit her second shot as the ball landed about 25 yards long and in the rough. An excellent approach shot for her third put Tseng within six yards of the hole while Hull's fading hopes for victory evaporated as she hit her third shot well short.

Tseng tapped in to card a one‑over‑par 73 and take her majors tally to three, having won the Kraft Nabisco Championship earlier this year and the LPGA Championship in 2008. She becomes the youngest golfer ever to win three LPGA majors.

Having appeared totally in control during the first 54 holes, in which she shot 68 in every round and dropped only one shot, she was much more edgy today and tears of relief flowed after she struck the final putt.

"I was very nervous, especially the last few holes," said the world No5, who pockets £260,000 in winnings. "I was so tired today, there was so much pressure and expectations – it was an unbelievable day for me. A four-shot lead on this golf course is nothing. She [Hull] really pushed me a lot and it was so close. She was pretty awesome."

With only one top-10 finish in 23 previous majors, it was a day of mixed emotions for Hull. "I am disappointed but there are also a lot of positives to take from this week," she said. "I never gave up but it's just a pity I couldn't make a birdie at one of the three long holes at the end."

Two Koreans, Choi Na-yeon and Kim In‑kyung, tied for third place on seven under and two more Koreans, Amy Yang and Seo Hee-kyung, were joined by this year's LPGA Championship winner, the American Cristie Kerr, in a tie for fifth on six under. Other notable performances included a final-round 66, six under par, by the Korean Park In-bee, who managed four birdies and an eagle to finish in a tie for sixth.

Melissa Reid was the first of the domestic players, a 70 giving her a four-over par total for 31st. Janice Moodie shot a 73 for a seven-over total and a tie for 55th.