Naas' Conor O'Rourke fired a superb, five-under-par 66 to take the first round lead in the West of Ireland Amateur Open Championship at Rosses Point.
Playing in the final group of the day, the 25-year old reigning St Andrews Links Trophy winner stormed to the turn in an immaculate five-under par 31 with birdies at the first, second, fifth, seventh and eighth.
He then birdied the 12th and bounced back from bogeys at the 14th and 17th with a tap-in birdie at the 18th.
"I just tried to keep things very simple," said O'Rourke who won last week's French International foursomes with Alps Tour professional Tommy O'Driscoll in Paris.
"I have gone through a bit of a rough patch lately, overcomplicating things a bit, so I tried to get back to basics with my fundamentals because I got a bit loose with those things."
The Naas ace birdied the first and second, picked up another shot by chipping dead at the long fifth, then reduced the downwind seventh to a sand wedge and six-foot putt.
After a superb 188-yard four-iron to 12 feet at the seventh, he picked up another shot at the eighth — the toughest hole on the course in yesterday's 15 mph west-north-west wind — then pitched dead to go six-under at the 12th.
Three putts at the 14th and three more from just off the edge of the 17th saw him fall back to four-under-par before he hit a lob wedge to two feet to set up a closing birdie.
Pleased to show form again after an up-and-down start to the year, O'Rourke said: "I was happy to tie for fifth in the South American Amateur. But I was disappointed in South Africa — I struggled with the conditions and lost a bit of confidence.
"But I have been playing better the last little while and today was good. I am just trying to keep thing simple and while today was good, especially on the front nine, it's a long week here so let's see how we go."
O'Rourke leads by two strokes from 17-year old qualifier Eoin Murphy from Dundalk, who came through a seven-hole playoff to earn one of four places in the starting field on Wednesday, then holed his second shot to the 18th for a closing eagle two and a three-under par 68.
The fifth-year student had to take a penalty drop from the wall at the second, which was the seventh extra hole in the qualifier when he was one of three players chasing the last two spots.
But made a five to get through as one of his rivals played a wrong ball and incurred a two-stroke penalty
The powerfully built two-handicapper Murphy took advantage of his good luck as he mixed three bogeys with four birdies before holing a 60-yard lob wedge for an eagle two at the 18th.
"It was a nice way to finish," said Murphy, who plays off 2.4. "It's my first men's championship and to be able to compete with these boys is great. Hopefully, I can do something solid tomorrow and get into the matchplay."
Playing alongside former West of Ireland champion Rory Leonard and multiple championship winner Michael Sinclair, Murphy opened with six pars, then birdied the seventh by hitting a 90-yard wedge stone dead.
After failing to get up and down for par at the ninth and 11th, he birdied three of the next four holes, two putting the 12th and then hitting wedges to two feet and eight feet at the 13th and 15th.
A three-putt from 20 feet saw him slip back to just one-under for the day before he finished in style.
"I am delighted it with it," said Murphy, who is a member of the Boys Development Panel and a former under 16 interprovincial.
"It was a good solid round of golf — I hit lots of greens and didn't do anything too mad until the 18th.
"And it was lovely to play with Michael and Rory, two great players who helped me along."
Just five players in the 134-man field broke par on a day when a 15 mph west-north-west wind gave the players a break on some of the tougher holes.
Ardee's Evan Farrell is third after a 69 with Dun Laoghaire's Ted Collins and Ballyhaunis' Andrew Hickey carding one-under 70s.
While Irish internationals John-Ross Galbraith and Tiarnan McLarnon shot rounds of 71 and 72 respectively, it was a tough day for some of the favourites.
While defending champion Jonathan Yates posted a 73, Irish Amateur Open champion Colm Campbell shot a 75, Co Sligo's Sean Flanagan a 77 and Castle's Alex Gleeson a 79 that featured a quintuple bogey nine at the 15th.
West of Ireland Amateur Open Championship (in association with Radisson Blu Sligo) Co Sligo GC (Par 71)
66 C O’Rourke (Naas)
68 E Murphy (Dundalk)
69 E Farrell (Ardee)
70 T Collins (Dun Laoghaire), A Hickey (Ballyhaunis)
71 J Greene (Portmarnock), C Woodroofe (Dun Laoghaire), J Hood (Galgorm Castle), L Donnelly (Kilkenny), W Russell (Clandeboye), P Coughlan (Moate), J Galbraith (Whitehead), M Reid (Galgorm Castle), H O’Hare (Fortwilliam)
72 G Lenehan (Portmarnock), S Bleakley (Shandon Park), N Crawford (Mourne), A Fahy (Dun Laoghaire), R Knightly (The Royal Dublin), B Anderson (The Royal Dublin), J Pierse (Portmarnock), A Lowry (Esker Hills), C Fairweather (Knock), J Walsh (Castle), C Rafferty (Dundalk), T McLarnon (Massereene), D Brady (Co. Sligo), P Cummins (Lurgan)
73 D Reddan Jnr (Nenagh), T O'Connor (Athlone), G McDermott (Carton House), D Foy (Laytown & Bettystown), R Mullarney (Galway ), T Ford (Co. Sligo), J McDonnell (Forrest Little), W Small (Tandragee), J Yates (Naas), A Grant (Dundalk), S Desmond (Monkstown), S Coulter (Warrenpoint)
74 J Sugrue (Mallow), R Moran (Castle), B Shally (Dromoland), M Nolan (Delgany), A HILL (Athenry), A Purdy (Ballyclare), R Abernethy (Dun Laoghaire), J Fletcher (Warrenpoint), S BRADY (Galway), B Loftus (Lahinch), D Holland (Castle), S Barker (Mourne), M McCormack (Ashbourne), G Fitzmaurice (Balcarrick), A Kearney (Castlerock)
75 H Foley (The Royal Dublin), S Ryan (The Royal Dublin), C Ryan (Dun Laoghaire), E Griffin (Waterford), R Cannon (Balbriggan), B Martin (Killymoon), M Morrissey (Co. Sligo), C Campbell Jnr (Warrenpoint), A McDaid (Palmerstown Stud), S Healy (The Royal Dublin), S Hogan (Nenagh), T Neenan (Lahinch), A Ryan (Thurles), A Considine (Lahinch), P Kerr (Royal Portrush), G Collins (Rosslare), A McCormack (Castletroy )
76 D Smith (Castle), S O’Connor (Luttrellstown Castle ), D Morgan (Carton House), D Murphy (Portarlington), B Best (Rathmore), J Logue (Hilton Templepatrick), M Fitzsimons (Ardglass), K Barry (Castlebar), P Flynn (Tramore), S Carter (The Royal Dublin), C Bring (Næstved), C Denvir (Elm Park), A Dillon (Carrickfergus), K McCormack (Portarlington), A Morris (Belvoir Park), R Dutton (Tandragee)
77 G Dunne (Co. Louth), E O'Brien (Clontarf), D Reidy (Co. Sligo), E McCormack (Galway Bay), D Jackson (Massereene), B McSweeney (The Royal Dublin), J Mulready (Castle), S Garrett (Portstewart), J Whelan (Newlands), D Lowry (Corrstown), M Sinclair (Knock), C Geraghty (Laytown & Bettystown), M McKenna (Dun Laoghaire), S McGlynn (Portmarnock), R Brazill (Naas), S Flanagan (Co. Sligo)
78 R Pierse (Grange), J Lyons (Galway), R Leonard (Banbridge), C Nolan (Galway), T Coffey (Slieve Russell), S McDermott (Co. Cavan), R O'Connor (Co. Sligo), D McAleenon (Lisburn), M Buggy (Castlecomer), M Looby (Greystones)
79 A Mulhall (Waterford Castle), S Cullen (Slieve Russell), J Blake (The Island), M Ryan Jnr (New Ross), G Young (Nenagh), M McKinstry (Cairndhu), D O'Neill (Carton House), S O'Hara (Co. Sligo), J Murphy (Kinsale), G MC MANUS (Co. Sligo), A Gleeson (Castle), A Gaynor (Co. Sligo)
80 D Brophy (Castleknock), G Smyth (Clonmel)
81 R Williamson (Holywood), A Pierse (Ballykisteen), P Carey (Nenagh), T Hackett (The Royal Dublin)
82 I Lynch (Rosslare), N McCann (Lurgan)
83 G McKenna (Fortwilliam), J Hadnett (Castletroy), S Underwood (Co. Sligo)
NR S Burns (Dromoland)