Jason Bohn fired an eight-under-par opening round of 64 to take a one-shot lead at the PGA Tour True South Classic before rain forced play to be suspended at Annandale Golf Club in Madison, Mississippi.
The Pennsylvania-born 39-year-old had eight birdies - including five on a strong back nine - in a bogey-free round before the weather intervened.
Luke Guthrie was provisionally second after signing for a 65, with fellow Americans JJ Killeen, Steve Lowery, Jason Gore and Willie Wood a further shot back in joint third along with Japan's Ryuji Imada.
A total of 65 players were still to complete their first rounds when play was called off.
Defending champion Chris Kirk was among them and was well placed, four under through seven holes.