Simon Thornton celebrated his first hole-in-one as a professional as he roared into a share of the lead after the third round of the Najeti Hotels Open at a blustery St Omer.
The Irishman was level par for the day and two over for the tournament after eight holes before he started a remarkable mid-round charge with a 30-foot putt for eagle at the ninth.
Better was to follow at the 206-yard par-three 11th, where he hit a "nice smooth" seven iron before jumping for joy after his ball took one bounce and rolled straight into the cup.
The world No 753 birdied the next and picked up another shot at the 15th, although his bid to match the course record of 64 fell just short when his eight-foot birdie putt at the last slid wide.
"That was obviously pretty good," joked Thornton. "I just played really well, hit some good shots and in weather like that you just have to keep straight and that's what I do well.
"I holed about a 30-footer for eagle at the ninth and then the hole in one. I was in between a seven iron and an eight iron and I hit a nice smooth seven and it was all over the flag, one big bounce and it just rolled in.
"There were a few high fives and shouts, it was my first one in a professional tournament so I was delighted."
Thornton's stunning round earned him the clubhouse lead, and he was later joined on four under by overnight joint-leader Tjaart van der Walt and Frenchman Baptiste Chapellan.
Van der Walt was on course to take a clear lead into the final round after following an eagle at seven with birdies at nine and 12.
But the South African struggled down the stretch for the second day running as he double-bogeyed the 16th and dropped another shot at the next as he returned a level-par 71.
Chapellan fired a solid three-birdie 69, while England's Seve Benson (70) cost himself a share of the lead after a bogey at the tough 16th following three birdies in seven holes.
Benson's compatriot Chris Lloyd is a shot further back after an erratic four-birdie, three-bogey 70, but Robert Dinwiddie stuttered to a 74 to slip three off the pace.
Dinwiddie, who shared the overnight lead with Van der Walt, dropped to one under alongside Jamie Elson, who had a sparkling run of five birdies in eight holes in a 68 that moved him 27 places up the leaderboard.