But Darren Clarke and Graeme McDowell face a fight to make the cut
Padraig Harrington will take a two shot lead into the second round of the Irish Open while Ardglass' Cormac Sharvin is right in the mix.
Harrington carded a blistering seven under par opening round 63 after hitting eight birdies to take a two-shot lead from the chasing pack. His opener was his lowest first round on the European Tour for 18 years.
Harrington finished in style in front of the large home crowds, getting up and down from a bunker on the par-five 18th for birdie.
Playing partner Ian Poulter also picked up a shot on the last, his third birdie in a row, to finish four under and end the day three behind Harrington.
He's alongside Ardglass professional Cormac Sharvin, who missed out on his European Tour card for this season by a single shot at Tour school in November.
The 26-year-old carded eight pars and a birdie on his opening nine before picking up four shots and a single bogey on the back for an impressive opening 66 - the same score as Shane Lowry.
If Sharvin can keep up that form, he could secure a spot at The Open. The top three unqualified players in this week's field will bag a spot at Royal Portrush, provided they can finish in the top 10 of Lahinch.
Sharvin is well clear of the other two Northern Irishmen in the field as both Graeme McDowell and Darren Clarke face a fight to make the cut.
Beginning their tournaments early on Thursday morning at Lahinch, Clarke carded a one over par 71 with McDowell a shot behind at two over.
McDowell could only card a single birdie, a two at the eighth, which helped alleviate the damage done by early bogeys at the second and third. A disappointing bogey six followed at the par five 12th to leave McDowell two shots outside the cut-mark of level par.
Clarke, meanwhile, produced a fine finish to get in at just one over par.
Three over with five to play, the 50-year-old birdied the 15th and the 18th holes.
The early clubhouse leaders were Thorbjorn Olesen, Wade Ormsby, Mike Lorenzo-Vera and Hyowon Park, who all carded early morning five under par rounds, later joined by English duo Lee Slattery and Eddie Pepperell and bettered only by Harrington.