Seamus Power is tied for sixth after a rip-roaring 68 but Shane Lowry's erratic start to the season continued with an opening 75 in the Wells Fargo Championship at Eagle Point.
Italy's Francesco Molinari fired eight birdies in a six-under-par 66 to lead by a stroke from Alex Noren, J.B. Holmes, Grayson Murray and Brian Campbell at the North Carolina venue.
But world No 70 Lowry has it all to do to avoid his second missed cut of the year after four bogeys in his first ten holes followed by a solitary birdie from four feet at the par-five 12th, left him tied for 115th.
While he hit 13 greens in regulation and nine of 14 fairway, Lowry's putting let him down badly as he used the blade 34 times, three-putting the fifth and eighth.
He also bogeyed the par-five sixth, where he hit his second shot into a water hazard while another shot went at the 166-yard 10th.
Graeme McDowell is tied for 31st after a one-under par 71 that saw him birdie the par-five 12th and sixth holes only to drop a shot at the eighth, where he couldn't make the green from the rough.
That leaves rookie Power as the leading Irishman on four-under par as he bids to move up the FedEx Cup standings and retain his PGA Tour card.
"Overall, I'm pretty pleased," said Power, who had just 25 putts. "Conditions were tricky with the breeze, but it was a little better than we were expecting. Overall it's a pretty good start."
A second place finish would guarantee Power's place in the season-ending playoffs, but he'll be gunning for a maiden win, a two-year exemption and a place in the Masters.
The West Waterford man began on the back nine and roared to the turn in four under 32, rolling in putts from 16 feet, two feet and 18 feet at the 10th, 12th and 13th to go three-under after four.
He then made a 12 footer at the 17th and another at the sixth before making another 12 footer for his fifth birdie of the day at the par-five sixth.
A birdie at the ninth would have given him a share of the lead with Molinari, but he closed with bogey, missing from just inside five feet for par after leaving himself a tricky chip from the fringe.
Despite that, he was more than pleased with with start and looking forward to consolidating his position in round two.
"The course is fantastic," Power said. "The manicuring is perfect, and it's a good layout. It's going to be a good test all week. I absolutely love it.
"I feel like I have a pretty good game plan for the course and where I want to hit it. You just have to stay patient.
"There are a lot of pins you just can't get near at the front of greens. But we will see what the weather does. Maybe that might change the course and something might get adjusted from there.
"For the most part, I will just try to keep doing the same things I was doing today."