Jordan Smith, Ross Fisher and Thomas Bjørn share the lead on 6 under par.
Clara man Shane Lowry has moved in to contention for this year's Horizon Irish Open at the K Club.
The 2009 champion shot a 4 under par 68 to finish day one firmly in the top ten.
Lowry opened with a birdie on the par five 10th, and would go on to make two more birdies and a bogey on the back nine.
He was set for a 67 by his 18th hole, but a bogey finish left him two shots off the current lead held jointly by Thomas Bjorn, Jordan Smith, and Ross Fisher.
Rory McIlroy is just a shot further back after carding a 69, while Padraig Harrington is even after seven and Tom McKibbin is one under each in the early stages of their first round in Kildare.
The Irish Open is brought to you by Keenan Bauer Motors Mullingar - Your home for Citroen and Honda in the Midlands – See Keenanbauer.com
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