The 2009 champion signed for a three-under par round of 69.
Shane Lowry is leading the home challenge after his opening round at the Irish Open at The K Club.
The 2009 champion signed for a three-under par round of 69, and is three shots off the clubhouse leader, Nacho Elvira.
Rory McIlroy is two shots further back, alongside Brooks Koepka on one-under.
The reigning Masters champion was frustrated after his group was put on the clock midway through his opening round:
In the afternoon groups today, Seamus Power is up to two-under.

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