David Skinns shot 5-under-par 67 on Saturday to jump ahead by a pair of strokes entering the final round of the Celtic Classic.
Skinns sits at 14-under-par 202 through 54 holes at the Lakes Golf Club.
Third-round leader Joel Dahmen stumbled to a 73 and dropped into a tie for second place at 12-under 204. He stands alongside Ryan Williams, who fired a 67.
Brandon Harkins (70), Yohann Benson (69), Wes Homan (70) and Mackenzie Hughes (71) share fourth at minus-8.
Dahmen's 3-stroke overnight advantage matched the largest 36-hole lead on the PGA Tour Canada this season, but it wasn't enough, as three bogeys and a double bogey at the par-3 17th marred Dahmen's card.
Skinns took advantage, thanks largely to a blistering closing stretch.
After notching three birdies and three bogeys on the front nine, Skinns birdied five of his last seven holes, including three straight from the 16th to jump into the lead entering the final round.
NOTES: The third round was completed Saturday morning after being suspended due to darkness with one group on the course Friday night ... This is the second straight new event on the PGA Tour Canada ... This is also the final event before the PGA Tour Canada Championship.