Scott Piercy and William McGirt lead the RBC Canadian Open at the halfway stage on 11 under par, one shot ahead of the field.
The duo had been among the front-runners after the first round, Piercy now having been at the top of the leaderboard at the end of both days as he seeks a second PGA Tour title.
The 33-year-old from Las Vegas, who won the Reno-Tahoe Open last year and was third on his latest start in the John Deere Classic, added a 67 to his opening 62 for a 129 total.
McGirt went round in 66 on the second day at Hamilton Golf and Country Club in Ancaster, Ontario.
“I’ve never been in this position out here,” said the American, who is a best-priced 15/2 with Bet365
to capture his maiden victory on the elite tour.
“I was in the next to last group at Tampa this year. It was a lot of fun. I’m looking forward to it.”
Piercy is disputing favouritism at a best price of 5/1 with Paddy Power
alongside Bo Van Pelt, who sits alone in fourth position two strokes off the lead and one behind third-placed Robert Garrigus (6/1 with Paddy Power
Among three men in a tie for fifth is Tim Clark, who matched the course record of 62 which Piercy also equalled in the first round.
The South African, who is gradually recapturing his best form after missing most of last year with a wrist injury, attributed his excellent round to the soft conditions.
He said: “Obviously with it being soft you can go at a lot of flags and make a lot of birdies.”
Clark initially struggled when he returned to action and in his first six starts this season he missed the cut four times and was disqualified from another event.
He added: “The only way to get better was to come out here and play tournament golf. I could feel I was getting better with every round I played.”