As he has done throughout an already stellar season, 16-year-old Jayden Tucknott rose to the occasion magnificently and despite falling behind early on to Jamie Blondel, the teenager moved up a gear to win four holes on the bounce from the seventh and from there he never looked back.
The momentum of their match changed as they crossed Mont Cuet Road with the champion 1 up heading to the seventh tee.
It was to be the last time Blondel led.
Tucknott, who had made mistakes on the fifth and sixth holes, reset himself and made back-to-back birdies that turned the tide in his favour.
He won the ninth with a par to go 2 up at the turn and Blondel then blocked his drive out of bounds on the 10th and the writing was on the wall.
The youngster was relentless from there and closed out the match on the 15th, by which time he was one-under par for his round.
Now the remaining junior in the field will face the remaining senior as Tucknott has a semi-final with Bobby Eggo to look forward to.
The top seed was involved in a cracking match with Sean Mills yesterday, which went the distance.
Eggo appeared to have the upper hand as he walked off the 11th green with a two-hole advantage, but Mills wiped that out over the 12th and 13th, making a long birdie putt on the latter.
The 11-time champion regained the lead on the par-five 14th where Mills went long with his third and was unable to save his par, but Eggo then uncharacteristically failed to capitalise on excellent approach shots to the next two holes and was disappointed to only halve both in pars.
Mills came within a whisker of levelling the match on 17 where his ball had a good look over the edge of the hole but decided not to drop and Eggo then sealed the victory with an outstanding tee shot on the last, which was playing directly into the chilly northeasterly wind.
The two quarter-finals in the bottom half of the draw both reached the 18th, too, with the 2019 and 2020 champions eventually progressing to set up an intriguing semi-final.
Jeremy Nicolle did it the hard way as he was 2 down to Steve Mahy with three to play in the anchor match, but he finished with three consecutive threes to pull off a memorable win.
Just 10 minutes earlier, Tom Le Huray had edged past Arthur Evans by the same scoreline in another see-saw encounter.
Evans had taken the early initiative thanks to a bright start before Le Huray won five holes on the trot from the eighth including birdies on 10 and 12 to give himself enough of a cushion to hold off his opponent’s fightback – but only just.