Ireland's Shane Lowry carded a bogey-free round of 65 to take a one-stroke lead after the first round of the RBC Heritage tournament in South Carolina.
Playing with a driver he used for the first time when he missed the cut at the Masters last week, Lowry carded birdies on all three par-fives to take a slender advantage.
Behind Lowry, four Americans — Trey Mullinax, Daniel Berger, Luke List and Ryan Moore — all carded five-under-par scores of 66.
Afterwards Lowry revealed the extent of the problems he has been having since starting the European season off on a high note with victory in Abu Dhabi.
He told a post-round press conference: “Pretty much my whole game felt good — I haven’t had that feeling in a while.
“I just played them nicely today. I’ve struggled off the tee quite a bit this year and I managed to find a new driver that I like. I hit that pretty good.”
Lowry had been struggling to break 70 all season and back-to-back rounds of 78 and 73 saw him miss the cut at Augusta.
He said he had tried at least 30 different drivers before finding the one which could help him reverse his recent fortunes.
“We’ve done a lot of work and I managed to find one I like,” he added. “Today was the first day that I hit the ball well off the tee.
“I’m happy with my golf. My scores haven’t been great of late, but I felt like I’ve been playing okay. So maybe this is a reward for the perseverance.”
Another Irishman, Séamus Powell, carded a three-under 68 alongside Northern Ireland’s Graeme McDowell, with Luke Donald and Ian Poulter among those two strokes further back.
Collated first round scores in the USPGA Tour RBC Heritage, Harbour Town GL, Hilton Head, South Carolina (USA unless stated, Irish in bold, par 71):
65 Shane Lowry (Irl)
66 Luke List, Daniel Berger, Trey Mullinax , Ryan Palmer , Ryan Moore
67 Kevin Na, Peter Malnati, Rory Sabbatini (Svk), Alex Noren (Swe), Sam Burns, Billy Horschel, Patrick Cantlay, Scott Piercy
68 Brian Stuard, Charley Hoffman , Graeme McDowell (NIrl), Hudson Swafford, Séamus Power (Irl), Chez Reavie, Emiliano Grillo (Arg), Dustin Johnson , Michael Thompson , Scott Langley , Rafael Cabrera-Bello (Spa), Jonathan Byrd
69 Bud Cauley, Jason Kokrak, Andrew Putnam, Vaughn Taylor, Zach Johnson, Andrew Landry, Matt Kuchar, Jonas Blixt (Swe), Kevin Streelman, Webb Simpson, Boo Weekley, Troy Merritt
70 Scott Stallings, Branden Grace (Rsa), Kyoung-hoon Lee (Kor), Joel Dahmen, Wyndham Clark, Denny McCarthy ,Jim Furyk, Marc Leishman (Aus), Bryson DeChambeau, Ian Poulter (Eng), J.J. Spaun, Luke Donald (Eng), Kyung Ju Choi (Kor), Mackenzie Hughes (Can)
71 Adam Schenk, Harold Varner III, Brian Gay, Austin Cook , Adam Hadwin (Can), Tommy Fleetwood (Eng), Eddie Pepperell (Eng), Kevin Kisner, Jordan Spieth, JT Poston , Chris Kirk , Chris Stroud, Xander Schauffele, Stewart Cink , Chesson Hadley, Brian Harman, Ryan Blaum, Adam Long, Cheng-Tsung Pan (Tai), Brandt Snedeker, Russell Knox (Sco), D.J. Trahan, Brandon Harkins, Matthew Fitzpatrick (Eng)
72 Colt Knost , Martin Kaymer (Ger), Cody Gribble , Harris English , Danny Lee (Nzl), Aaron Baddeley (Aus), Cameron Smith (Aus), Rod Pampling (Aus), Ernie Els (Rsa), Patton Kizzire , Ryan Armour, Morgan Hoffmann, Nick Taylor (Can), Brice Garnett , Sungjae Im (Kor), Anirban Lahiri (Ind)
73 Satoshi Kodaira (Jpn), John Augenstein , Benjamin Silverman (Can), Si Woo Kim (Kor), Charles Howell III, Ollie Schniederjans, Bill Haas, Russell Henley, Jason Dufner, Sam Saunders, Mark Anderson, D.A. Points, Abraham Ancer (Mex), Whee Kim (Kor), Ted Potter, Jr. , Michael Kim , Keith Mitchell , Tyler Duncan
74 Francesco Molinari (Ita), Richy Werenski, Nick Watney, Justin Harding (Rsa), Charl Schwartzel (Rsa), Byeong-Hun An (Kor), Martin Laird (Sco), Danny Willett (Eng), Cameron Champ , Corey Conners (Can)
75 Matt Wallace (Eng), Peter Uihlein, Jim Herman
76 Ray franz Jr, Beau Hossler, Lucas Glover, Kelly Kraft, Alex Cejka (Ger), Tom Hoge
77 Scott Brown
82 Roger Sloan (Can)
