|First round leaderboard|
|-6 Lowry (Ire); -5 Mullinax (US), Berger (US), List (US), Moore (US), Palmer (US)|
|Selected others: -3 McDowell (NI), Johnson (US); -1 Donald (Eng), Poulter (Eng); Level Pepperell (Eng), Fleetwood (Eng), Fitzpatrick (Eng), Knox (Sco); +3 Molinari (Ita), Laird (Sco), Willett (Eng)|
Ireland's Shane Lowry hit a six-under-par 65 for a one-shot lead after the first round of the RBC Heritage as Francesco Molinari struggled to bounce back from his Masters disappointment.
Molinari had led going into the final round at Augusta on Sunday, but collapsed on the back nine as Tiger Woods won his 15th major title.
The Italian carded an opening-round three-over-par 74 at Hilton Head.
World number one Dustin Johnson finished on three under par.
Northern Ireland's former champion Graeme McDowell is also at three under, while England's Luke Donald and Ian Poulter are two shots back.
American three-time major winner Jordan Spieth and English trio Matthew Fitzpatrick, Tommy Fleetwood and Eddie Pepperell are all at level par.
"Pretty much my whole game felt good," Lowry said after his bogey-free round. "I haven't had that feeling in a while. So it's kind of nice."
Wind and thunderstorms are forecast for Friday's second round.
"You know the forecast is not going to be great," added Lowry. "Yeah, I've seen it and knew this was my chance to go out and shoot a good number."