The Englishman entered the day in a share of top spot and turned in 35 to get to 12 under.
The overnight six way tie at 11 under soon became a five way tie at 12 under but Højgaard was the first player to strike out on his own.
After taking advantage of the par five third, the 18-year-old put his tee shot to four feet on the fifth to hit the front on 13 under.
A bogey on the sixth then brought him back to the pack at 12 under.
Sordet birdied the second and fourth before a very long putt at the fifth put him in a share, while Shinkwin birdied the third but gave the shot straight back on the next.
Valimaki had birdied the second but found sand off the tee at the fourth for a bogey before capitalising on the par five seventh.
Shinkwin left himself 12 feet for a birdie and a share at the eighth but Valimaki put his tee shot to four feet and hit the front on his own.
Højgaard three putted from just off the ninth green to drop to 11 under and Sordet slipped into that group when he three putted the tenth.
Valimaki found sand with his second at the ninth and flew his third over the green from a poor lie, signing for a double bogey to leave Shinkwin on his own at the top.
Migliozzi had birdied the first but gave the shot straight back on the second before making the most of the third and putting an approach to three feet at the fourth. He then bogeyed the eighth to fall back.
Saddier recovered from a bogey-bogey start with gains on the fourth, sixth, seventh and eighth, while Smith had birdies on the second and sixth.
Stone made a bogey on the second but hit back on the next to turn in level par.