Chile's Hugo Leon carded a brilliant five under par 67 to grab the clubhouse lead in the East of Ireland Amateur Open at Baltray.
The US based Latin American went to the turn in five under par 32 after birdies at the second and third with and eagle at the sixth and another birdie at the seventh.
The 21-year-old, who is playing on a links course for just the second time after finishing tied for 35th in the Irish Amateur Open at Portmarnock last month, dropped his only shot of the day at the 421-yard 13th but he got it back at the tricky 16th and parred his way home.
Defending champion Jim Carvill from Warrenpoint signed for a disappointing five over par 77 but fellow Ulstermen Darren Crowe and Jonny Caldwell hit rounds of 69 to trail Leon by just two shots with half the field still to finish.
Beaten West of Ireland finalist Paul O'Hanlon of the Curragh hit a two under par 70 to match Alan Glynn of Porter's Park while veteran Barry Reddan signed for a level par 72 in perfect conditions at the famous County Louth club.
East of Ireland championship, Co Louth (Par 72)
67 H Leon (Chile)
69 D Crowe (Dunmurry), J Caldwell (Clandeboye)
70 A Glynn (Porters Park (ENG), P O'Hanlon (Curragh)
71 G Lawlor (Citywest)
72 J Fox (Portmarnock), J Timoney (Headfort), G Hall (Edenderry), K Ritchie (Quailridge, USA), A McKinley (Shandon Park), L Morris (Stonebridge, USA), B Reddan (Co. Louth), S Grant (Birr)
73 M Lavelle (Belmullet), B McCarroll (Ballyliffin), J Hughes (Douglas), R Branigan (Co. Louth), B O'Connor (Hermitage), G Bowden (Hermitage), S Power (West Waterford), J Somers (L'town & B'town), C Curley (Newlands)
74 A McAllister (Portmarnock), J McGinn (L'town & B'town), A Pitcher (The Island), R Evans (Moyola Park), P McGibney (Pheasant Run, USA), P Murray (Limerick), G Mallon (North West), J McKinstry (Cairndhu), D Rawluk (The Island)
75 D McNeill (Ballybofey), D Ruddy (Thurles), N Heather (Portmarnock), G Carew (Edenderry)
76 D O'Brien (L'town & B'town), M King (Athenry), N Grant (Knock), B Walton (The Island), G Nugent (Kilkenny), A Harty (West Waterford), S Crowe (Dunmurry), R McCarthy (The Island), M Poucher (Castle), K Stack (Dungarvan)
77 A Dowling (Hermitage), J Waldron (Muskerry), C Martin (Kilkenny), A Condren (Greystones), S O'Flaherty (Hermitage), J Carvill (Warrenpoint), C McAleavey (Banbridge), D Boyle (Cruit Island), S Doherty (Ballyliffin)
78 A Boyle (Hollystown), M Reck (Lucan), K Purcell (Dun Laoghaire), C O'Connor (Corrstown), A O'Callaghan (Douglas)
79 N Armstrong (Clandeboye), J McCarthy (R. Waterloo (BELG)), D Scully (Galway)
80 S Shaw (Lisburn), M Campbell (Stackstown), T Kelly (Balcarrick), J Heaslip (Ballyclare), P O'Brien (Lucan), N O'Briain (Royal Dublin)
81 S O'Donnell (Portarlington), A McCormick (Scrabo)
83 P Connolly (Clontarf), B McSweeney (Woodbrook), M Rowe (Athlone), J McDermott (Stackstown) 84 A McAuley (Ardee)
85 P Cowley (Cork)
89 R O'Reilly (Headfort)