Jaco Ahlers fired a 9-under 63 on Friday to grab a 2-stroke lead at the end of two rounds of the Dakota Dunes Open.
Ahlers, who is seeking his first career win on the PGA Tour Canada, finished 36 holes at Dakota Dunes Golf Links at 16-under-par 128.
Nick Taylor matched Ahlers' 63 to move into a share of second place with Doug McGuigan at 14-under. McGuigan shot an 8-under 64 during his second round.
Matt Hoffman (67) and Wil Collins (65) are tied for fourth at minus-13, while Joel Dahmen matched the low round of the day with a 10-under 62 to move into sixth place at 12-under 132.
First-round leader Danny Sahl tripped to a 2-over 74 to fall into a large group of players tied for 38th place at 7-under.
Ahlers raced out of the gate with back-to-back birdies at the first and second before tripping to a bogey at the third.
The South African, however, bounced right back with three straight gains from the fifth to make the turn at 11-under.
Ahlers moved to 13-under with another pair of birdies at the 12th and 13th, and later followed a birdie at the 16th with an eagle at the last to head into the weekend with a 2-stroke cushion.
NOTES: The cut line fell at 6-under-par 138, with 67 players advancing to the weekend ... The 6-under cut line tied a PGA Tour Canada record, matching the lowest cut line since the 2008 ATB Financial Classic ... Christopher DeForest also shot a 62 on Friday. He is among the group tied at 7-under.