Jim Furyk matched the course record at Royal Montreal to earn a share of the lead on day two of the Canadian Open.
The American carded seven birdies in a bogey-free round of 63 to join Tim Petrovic at the top of the leaderboard on 10-under-par after 36 holes.
Petrovic, who has missed the cut in his previous five events, followed up his 64 on Thursday with a 66 to continue his upturn in form.
Michael Putnam had shared the lead with Petrovic on Thursday, but he could only record an even-par 70 on his way to falling four strokes off the pace.
Home favourite Graham DeLaet matched Furyk's effort with a 63 to climb to third alongside Kyle Stanley, who also reached eight-under at the halfway stage of the competition.
