Clément Sordet fired the lowest round of his European Tour career to set the clubhouse target on day one of the Nordea Masters at Hills Golf Club.
The Frenchman fired a bogey-free 62 to get to eight under and open up a two-shot advantage over Scotland's Scott Jamieson and Englishman Lee Slattery.
That score eclipsed the 64 he fired en route to his only European Tour top ten at the season-opening UBS Hong Kong Open, and beat the 63 he shot as an amateur at the 2014 Le Vaudreuil Golf Challenge as an amateur on the Challenge Tour.
Sordet is no stranger to the winner's circle, winning four times on the Challenge Tour including twice last season as he earned his card for a rookie campaign on the European Tour.
Home favourite Christofer Blomstrand and Finn Tapio Pulkkanen were five under.
Sordet got off to a flying start with four birdies and when he added further gains at the 11th, 12th and 13th he was seven under and held a two-shot lead.
Jamieson briefly joined him at the summit but fell back and when Sordet got up and down from the sand on the par-five last, his cushion was restored.
The 25 year old's effort beat the previous course record by four shots but with placing on the fairways in play, he will be denied his place in the history books.
Jamieson started on the tenth and he recovered from a dropped shot on the 11th with birdies on the 12th, 14th, 15th, 16th and 18th to turn in 30.
Another birdie came at the second and when he put an approach to five feet on the third and holed a 29-foot right-to-lefter on the fourth, he shared top spot.
The 34 year old made a smart par save on the par-three next after nearly finding the water but the erratic iron play continued with bogeys on the sixth and seventh before he bounced back with a gain on the eighth.
Slattery birdied the third and fourth but really made his move after the turn with gains on the 12th, 13th, 14th and 16th catapulting him up the leaderboard.
A bogey on the 17th stalled his momentum but he finished with a birdie on the last.
Blomstrand started with a bogey but bounced back in emphatic fashion as he birdied the second, eagled the par five third and made further gains on the fourth and sixth to turn in 32.
One more birdie would follow on the 12th in his lowest opening round of the season.
Reigning Road to Oman champion Pulkkanen made all his birdies on the back nine, picking up shots on the 11th, 12th, 13th, 16th and 18th before finishing with nine pars.
South African Thomas Aiken, English pair Daniel Brooks and Paul Waring, Australian Lucas Herbert, Dane Søren Kjeldsen and Frenchman Matthieu Pavon were four shots off the lead.
