Patrick Reed struck four birdies and an eagle in the final six holes to fire an eight-under 65 and take his place at the top of the first-round leaderboard at the Hyundai Tournament of Champions in Hawaii.
The four-time PGA Tour winner was well down the leaderboard after turning on two under, but was in scintillating form on the back nine, reeling off birdies at the 13th, 14th and 15th holes.
After hitting par at the 16th, he was back in the red with another birdie before bringing his round to a close with an eagle on the par 5 18th.
He came on in just 31 shots, six under par.
Reed's playing partner and world number one Jordan Spieth finished one shot behind on seven-under after another blemish-free round, registering seven birdies.
Brandt Snedeker, J.B Holmes and Danny Lee are all placed on six under while two-time Masters champion Bubba Watson is a further two behind after shooting 69.
World number two Jason Day did not enjoy as productive days as Reed and Spieth, but is still well-placed thanks to a bogey-free three under.
Scotland's Russell Knox is the best-placed Brit on two under while Graeme McDowell struck two double bogeys in his two-over-par 75.