Shane Lowry is among those who tees off at the RBC Canadian Open in Ontario today.
After missing the cut at The Open last week, Lowry parted company with his long-time caddy Dermot Byrne.
His brother Alan will be on the bag in Oakville this week.
Graeme McDowell and World Number One Dustin Johnson are also in the field.
Seamus Power tees off shortly.