Jeunghun Wang was in brilliant form as he established a three-shot lead in the third round of the 100th Open de France at Le Golf National.
The South Korean had back-to-back wins in May at the Trophée Hassan II and the AfrAsia Bank Mauritius Open but has struggled to rediscover that level as he adjusts to life on the European Tour.
He looked very comfortable on Saturday, though, as he birdied four of his first eight holes to get to nine under and open up a three-shot cushion to Thongchai Jaidee.
Home favourite Mathieu Decottignies-Lafon was then a further two shots back alongside Denmark's Lasse Jensen and South African Brandon Stone.
There was a five-way tie for the lead coming into day three and that soon became six as Nicolas Colsaerts birdied the first to get to five under.
But as many of the overnight challengers, including World Number Four Rory McIlroy, began to fall back, Wang found another gear.
The 20 year old birdied the second but Colsaerts chipped in on the fourth to join him before making a double-bogey on the next after getting in bunker trouble.
A birdie at the third from Mikko Ilonen kept him in touch but Wang rolled in from six feet on the fourth and then holed from the fringe on the fifth.
Ilonen got in serious trouble in the rough on the fifth to sign for a double-bogey and when Wang rolled in a lengthy effort on the seventh, the lead was up to four shots.
Jaidee opened with five pars but rolled in a sensational 55-footer on the sixth to cut the gap back to three.
Decottignies-Lafon was three under for his round through 13 holes while Jensen was two under after ten. Stone had two birdies and a bogey in six holes.
An eagle on the 14th moved Martin Kaymer into the group at three under alongside Colsaerts, Francesco Molinari, Andy Sullivan and Bernd Wiesberger.
McIlroy was a further shot back after dropping three shots in his first three holes, with Lee Westwood also at two under having set the clubhouse target with a 67.
