PERTH, Australia, Oct 19, 2012 (AFP) - The 20-year-old Grillo, in his first year as a pro, came to Australia trying to improve his lowly 516 world ranking and to keep his European Tour card for 2013.
But after rounds of 66 and 67 in the European Tour co-sanctioned event at the Lake Karrinyup course, the former top amateur is poised for his maiden professional victory.
"My goal this week was having a good one to keep my card for next year. I mean, if I can win, awesome," Grillo said.
Grillo led American Bo Van Pelt (70-67) and local professional Jason Scrivener (68-69).
Van Pelt flew the flag for the tournament's big names with compatriot Jason Dufner working his way into the event with a well-compiled 67, which left him trailing Grillo by five shots.
Grillo has become popular with local galleries and he thrilled them with two eagles on the front nine -- holing a 100-metre wedge shot from light rough and holing a bunker shot.
The Argentine has never led a professional event before although he did lead his country Open championship at the halfway mark when he was an amateur.
His father introduced him to golf as a nine-year-old and by the time he was 14 he was playing for his country in senior events.
He has played in the amateur Eisenhower Cup for Argentina and on his only other trip to Australia he finished well back in the World Amateur Golf Championship in Adelaide.
Grillo attended the IMG Golf Academy in Florida for a number of years before turning professional. He wants to join the USPGA Tour but has started his professional career in Europe.
England's Paul Casey carded 75 to be nine shots off the pace but 2011 Masters Champion Charl Schwartzel had 76 to miss the halfway cut by a shot.
The South African grimaced when he pushed a short putt on the last to the right to deny him a spot in the field over the weekend.
"I've really enjoyed my time in Perth. Hopefully, I can come back soon to redeem myself," Schwartzel said.
World No.10 Dufner felt his round could have been at least a couple of shots better.
"I had a really nice round. Could have been a really special round. I did not play the par fives well but it's good to get a nice round under my belt and look forward to the weekend," he said.
Van Pelt is playing well in spite of having three weeks off and losing his clubs on the flight to Australia.
"It's a very challenging golf course and it's fun to play. I'm very excited to be in a decent position going into the weekend," the world No.24 said.
The American said the course reminded him of Innisbrook, in Tampa, Florida, where he is a regular.
"I've just felt comfortable from the time I got here," he said.
Scores after the second round of the $Aus2 million ($2.04 million) EPGA-sanctioned Perth International at Lake Karrinyup (par-72) in Perth on Friday (Australia unless stated):
133 - Emiliano Grillo (ARG) 66-67
137 - Bo Van Pelt (USA) 70-67, Jason Scrivener 68-69
138 - Max McCardle 68-70, Michael Hendry (NZL) 65-73, Jason Dufner (USA) 71-67, Alejandro Canizares (ESP) 65-73
139 - Peter Cooke 73-66, Stephen Dartnall 72-67, Robert Coles (ENG) 71-68, David Howell (ENG) 71-68, Richard Bland (ENG) 70-69
140 - Craig Lee (SCO) 70-70, Mark Brown (NZL) 71-69, Ashley Hall 68-72, Alastair Forsyth (SCO) 70-70, Rhys Davies (WAL) 68-72, Andrew Johnston (ENG) 67-73
141 - Knut Borsheim (NOR) 70-71, Greg Chalmers 68-73, Andrew Dodt 68-73, Matthew Millar 71-70
Selected scores:
142 - Jin Jeong (KOR) 70-72, Paul Casey (ENG) 67-75, Thomas Petersson (SWE) 70-72, Edouard Dubois (FRA) 71-71
143 - Sam Little (ENG) 72-71, Edoardo Molinari (ITA) 71-72, Scott Jamieson (SCO) 72-71.
145 - Matthew Baldwin (ENG) 74-71, Jamie Moul (ENG) 70-75, Ignacio Garrido (ESP) 74-71, Federico Colombo (ITA) 71-74, Tommy Fleetwood (ENG) 75-70, Steve Webster (ENG) 72-73
146 - Oliver Wilson (ENG) 73-73, Mikael Lundberg (SWE) 75-71, Thomas Norret (DEN) 72-74
147 - Andy Sullivan (ENG) 72-75, Markus Brier (AUT) 70-77, Charl Schwartzel (RSA) 71-76, Lorenzo Gagli (ITA) 72-75
148 - George Murray (SCO) 77-71, Andrea Pavan (ITA) 72-76, Gareth Maybin (NIR) 77-71, Joakim Lagergren (SWE) 78-70
150 - Gary Boyd (ENG) 73-77, Johan Edfors (SWE) 77-73, Carlos Del Moral (ESP) 69-81, James Kingston (RSA) 76-74
151 - Oscar Floren (SWE) 77-74
152 - Peter Hedblom (SWE) 77-75
153 - Mikko Ilonen (FIN) 77-76
154 - Daniel Denison (ENG) 75-79
The final cut was made at +2 (146). 72 players made the cut.