Seventeen -year-old Amy Boulden from Wales will play 18-year-old Alexandra Bonetti from France, and it will be an all-England affair in the second tie between defending champion Kelly Tidy, 19, from Lancashire against 16-year-old Lauren Taylor from Buckinghamshire.

Amy Boulden ended the great run by South African team player Kim Williams who had beaten local favourite Stephanie Williams by 4 and 3 in the morning’s third round.

Boulden is the highest qualifier (9th) to reach the last four. She has been chosen to play for Great Britain and Ireland in both the Astor Trophy tournament at Fairhaven GC next week and the Vagliano Trophy in her native Wales – Royal Porthcawl , to be precise - the week after that.

“I came to Northern Ireland playing well and I’ve been able to keep my form going, but I didn’t actually strike the ball as well as I can against Kim. Fortunately, I chipped well and I holed out well, and that counts for a lot in match-play,” said club professional’s daughter Amy, born and bred in Llandudno in North Wales and a member of the Maesdu club.

Boulden reckoned she was four or five under par in beating the South African.

The tone for the match was set as early as the first hole which was halved in birdie 3s. Amy never looked back after holing a 12-footer for a birdie 3 to go one up at the fifth.

She landed another telling blow by holing a 25ft putt for an eagle 3 at the seventh, getting home at this 428yd hole with a drive and a four-iron. Williams, incidentally, had a cast-iron birdie 4 trumped here.

But the South African got an eagle of her own at the long ninth where she holed from 20ft for a 3 while Amy just missed with her eagle putt.That cut Boulden’s lead to one hole at the turn but it was to prove Williams’ first and only success of the match.

The 10th was halved in birdie 4s before Amy went two up at the short 11th where Williams was bunkered.

Two up became three up at the 13th where Boulden got up and down from a bunker for winning par 4 while Williams, who had missed the green, could not match that.

The South African three-putted at the short 13th, going four down to a pitch-and-putt par 3 by Boulden.

It was all over at the next hole with Boulden 15ft from the flag with two shots. She did not have to play another. Williams missed the green and eventually conceded the hole and the match to her classy Welsh opponent.

Amy’s opponent, teeing off at 8.30am, is Alexandra Bonetti, the tall Parisienne who beat South Africa’s Illiska Verwey with a superb approach shot at the 19th after a titanic struggle in which the lead changed hands repeatedly over the closing holes.

There must be something about the air in Northern Ireland that brings out the best in Alexandra. Last August, she won the British girls’ open amateur championship at Royal Belfast Golf Club.

Since then she has finished second in a Ladies European Tour event in Morocco. In August, Bonetti is bound for America to enrol as a student at Texas Christian University.

Three times the French girl took a one-hole lead on the outward half and three times Illiska Verwey pulled her back to square.

The 10th was halved in birdie 4s and the next three holes were halved as the battle for supremacy continued, with birdies necessary to win holes. Verwey birdied the short 14th to edge ahead but Bonetti levelled it immediately with a birdie at the 15th.

Bonetti made a rare mistake on the greens in three-putting the 16th to go one down but she was back in the groove on the 17th green were she holed from 10ft for a birdie 4 to square the match. The long 18th was halved and Bonetti played a magnificent six-iron approach under pressure at the 19th. Her ball came to rest little more than a couple of feet from the hole for an almost-certain birdie 3, which was eventually conceded by Verwey when she failed to hole out in 4.

Title-holder Kelly Tidy (Royal Birkdale), finding last season’s form at just the right time, was six under par for the day in reaching the semi-finals for the second year in a row.

In an all-England quarter-final, she beat good friend Charlotte Wild (Mere) by 4 and 3 with three under par figures.

Kelly was out of the traps like a greyhound to stand two up on the third tee, having won the first with a par and the second with a two-putt birdie 4.

Tidy three-putted the fifth to see her lead halved but she immediately went back to two up with a par at the sixth where Wild three-putted Kelly holed from 8ft for a winning birdie 3 at the eighth but lost the ninth and was back to “only” two up at the turn.

That quickly became three holes of an advantage again when she pitched and putted for a birdie 5 at the long 10th.

Tidy played a great approach shot to within 5ft of the flagstick to win the 12th with a birdie 3 to go into a four-hole lead. Three successive halves ended the contest.

“I hate playing girls I know well – and I hear that I have to go through it again on Saturday morning against Lauren, having had to beat Kelsey MacDonald then Charlotte,” said Kelly who is a couple of inches taller than she was when she won the title at Ganton 12 months ago.

Lauren Taylor, at 16 years of age, is playing the golf of her young life. She earned herself a semi-final place against Kelly Tidy by beating Perrine Delacour, the French player who won the British girls title at West Lancs GC to years ago, by 4 and 3.

Lauren was four under par for the match and five or six under for another momentous day for the Woburn youngster.

“I’m not doing anything special. Honest! My dad and I decided that I would relax and just let it happen in this championship. Maybe in the past I’ve just tried too hard and not played my best,” said Lauren

She surged into a three-hole lead over the outward half against Delacour, birdieing the eighth to go three up and then halving the ninth in birdie 4s.

Delacour must have hoped she had turned the tide when she holed from 10ft for a winning eagle to Lauren’s birdie at the long 10th but Taylor was not to be denied.

When won the 13th with a par, when Delacour was bunkered, and the short 14th with a five-iron tee shot to within 3ft of the stick.

Four up with four to play, Lauren clinched another notable win wit a birdie 3 at the 15th but it was recorded as a halved hole for a 4 and 3 win.