Kevin Streelman fired a nine-under 63 to open up a two-shot lead after the opening round of the Sanderson Farms Championship, where Ian Poulter lies seven strokes off the pace.
Streelman took advantage of low scoring conditions to mix 10 birdies with a sole blemish in Mississippi, moving ahead of a three-way tie for second which includes Ireland's Seamus Power.
Beginning on the back nine, Streelman birdied three of his first four holes before picking up strokes at the 15th and 17th to reach the turn in 31.
A hat-trick of gains from the first came to an end with a three-putt bogey at the fourth, only for the American to roll in a nine-footer at the sixth and hole a birdie from a similar distance at his final hole.
"It was just a ton of fun for me, it's what we do this for," Streelman said. "There are certain days when things click. I'm hoping that feeling can continue for the rest of the week."
Power and Trey Mullinax both posted bogey-free 65s to share second with Carl Pettersson - who holed out for a 162-yard eagle late in his round - with Lucas Glover part of the group a further shot adrift.
World No 74 Chris Kirk is the highest ranked player at The Country Club of Jackson and opened with a five-under 67, as Poulter continued his return from injury by mixing four birdies with two bogeys.
The Englishman, who missed four months of the year with a foot injury, reached the turn level-par before opening his second nine with back-to-back gains.
Defending champion Peter Malnati shot a one-under 71, with 100 of the 132-man field shooting even par or better during the opening day.
Watch the Sanderson Farms Championship throughout the week live on Sky Sports 4 - your home of golf. Live coverage begins on Friday from 7.30pm.