The Clara man will be hoping to defend his title.
There are four Irish players in the field for the BMW PGA Championship - the flagship event on the DP World Tour.
Padraig Harrington has bogeyed the first hole, while Rory McIlroy on the first.
Defending champion, Offaly's Shane Lowry is about to tee off and Tom McKibbin has a start time of 11.55.
All of Europe's Ryder Cup players are in the field, including Masters winner Jon Rahm.
England's James Morrison is the early leader on 2 under par.
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