Stuart Appleby

Australian pair Stuart Appleby and Gavin Coles are just three shots off the lead after the opening round of the Canadian Open.

The duo carded rounds of five under 65 to be tied for fifth place behind American Scott Piercy, who hit a course record 62.

On a rain-soaked day in Ontario, Piercy hit two eagles and five birdies in an eight-under-par round at the Hamilton Golf & Country Club, to lead compatriot William McGirt and England's Greg Owen by one stroke.

Fellow American Robert Garrigus was a shot further back in fourth, while Appleby and Coles sunk six and five birdies respectively in their impressive rounds.

They share fifth alongside American duo Troy Matteson and Bo Van Pelt, Venezuelan Jhonattan Vegas, South African Charl Schwartzel and Fijian Vijay Singh.

Meanwhile, it was a difficult first day for British Open champion Ernie Els.

The South African had two bogeys on the front nine and a triple bogey on the 11th hole to end the day at two-over-par 72.

Adam Hadwin closed the round as Canada's best-placed golfer in a tie for 12th after recording a four-under-par 66 round.

American Matt Kuchar, the highest-ranked player at the event at number nine, shot a three-under-par 67 to sit five shots behind the leader, while defending champion Sean O'Hair endured a miserable day, firing a five-over-par 75 to languish in 144th alongside Australian Matt Jones.

Australia's Steven Bowditch finished one-under with Nick O'Hern, while 2009 champion Nathan Green managed an equal-par round with Mathew Goggin to head into round two tied for 66th.

Robert Allenby sunk a birdie on the 16th but bogeyed on the second and double bogeyed on the 11th as he finished two-over-par 72.