Naas' Conor O'Rourke fired a 69 and Castle's Alex Gleeson and Lisburn's Paula Grant a pair of two under 70s to leave them inside the top 10 in their respective South American Amateur Open Championships in Argentina.
O'Rourke's three under par effort featured four birdies and just one dropped shot and was good enough for a five-way share of second place, albeit four strokes adrift of Argentina's Carlos Montenegro, who carded a seven under par 65 at Martindale Country Club in Buenos Aires.
AIG Irish Close champion Gleeson is tied for seventh after making an eagle two, two birdies and two bogeys for his 70.
Starting on the back nine, the UCD man birdied the 11th and bogeyed the 14th to turn in level par, then followed a birdie at the fifth with a bogey at the sixth before making an eagle two at his 17th hole, the eighth.
Grant lies third in the women's championship after making four birdies and two bogeys in her 70, leaving her just two shots behind Mexico's Isabella Fierro, whose four under 68 gave her a one-stroke lead over Argentina's Ela Anacona.
As for Clandeboye's Jessica Ross, she is tied 20th after a four over 76 featuring an eagle three, one birdie, five bogeys and a double bogey six.