Padraig Harrington shot a superb 7-under-par 63 for his lowest opening round on the European Tour in 18 years to take a one-shot lead on the first day of the Irish Open on Thursday.
Home favourite Harrington, 47, had eight birdies and a lone bogey to sit a shot ahead of South Africa's Zander Lombard, with a group of seven players tied for third at Lahinch Golf Club.
"I like playing links golf. I knew coming into this run that if I get my head in the game I have an advantage," said Harrington, participating in only his second European Tour event of the season following a broken wrist.
"Today, I did a lot of good things, holed a few putts here and there and got a few breaks. I didn't expect 63 out of it. It would definitely be up there with one of the simplest, easiest, most pleasant days ever on the links.
"I know I don't have to play as well as that for the next three days. It would be nice if I did but we'll go out there and try and do more of the same. If nothing good happens for the next three days, so be it. I know I'm on the right track."
Harrington, the 2007 champion, fired three straight birdies starting from the eighth hole but had a setback at the 11th where he missed the green for his only bogey of the day.
However, the three-times major winner recovered to add further gains on the next two holes and finished with another birdie on the final one, much to the delight of the crowd.
Two-time major winner Martin Kaymer and Ireland's Shane Lowry sit one shot back in a nine-way tie for 10th place. Kaymer didn't give much to cheer about for most of the day before making birdie at the each of the final three holes to card a first-round 66.
Lowry shot five birdies on the way to a first-round 66, including a lucky shot at 14th when his shot from the deep rough took a lucky bounce to the green, careering into the flag stick and landing just a few feet from the pin for a tap-in bridie.
England's Tommy Fleetwood also went under par to stay in touching distance of the lead, carding a 67 to sit 3 under, tied 19th.
Northern Ireland's Rory McIlroy is not competing this week, missing the tournament for the first time since 2007, as he continues his preparations for the British Open at Royal Portrush, Northern Ireland later this month.