Americans Briny Baird and Brian Gay shared the clubhouse lead after a weather-affected opening day of The McGladrey Classic in Georgia.
The duo both fired opening-round 63s to sit seven-under after fog had delayed play by almost two hours in the morning.
The pair were overhauled by compatriot George McNeill at the top of the leaderboard later in the day as he reached eight-under through 16 holes before darkness brought an end to proceedings.
McNeill - who made eight birdies and not a single bogey - will have to return early on Friday morning to complete his first round along with 50 other competitors.
Former US Open champion Webb Simpson was one of five players two shots back alongside fellow American Kevin Kisner, Kevin Chappell, South Korean Seung-yul Noh and Robert Garrigus (13 holes).
Baird has not recorded a win in his previous 364 appearances on Tour but could break that duck this week after a stunning start at Sea Island.
The 41-year-old recorded a flawless round as he birdied the second, third and fourth holes before hitting another hot streak at the end of his day with further birdies at 14, 15, 16 and 17.
Gay did have a blemish on his card as he dropped a shot on the 12th but he countered that with eight birdies in calm conditions.
A large group has gathered on four-under including Jonathan Byrd, Camilo Villegas, John Senden and Carl Pettersson.
Major champions YE Yang, Retief Goosen and Ben Curtis were all on two under having completed their rounds while defending champion Tommy Gainey was level par through four holes.