Sawt Falasteen - Riley, Gordon lead by one at Sanderson Farms PGA

Riley fired a bogey-free six-under-par 66 while Gordon made seven birdies and one bogey as he moved to the top of the leaderboard at the Country Club of Jackson.

Gordon and Riley, who have yet to win on the PGA Tour, are one ahead of seven players tied for third on five under.

A victory for Riley this weekend would carry extra significance for the 25-year-old world number 69, who was born and raised in Mississippi and played the Country Club of Jackson course regularly as a schoolboy.

"I do have fond memories here individually and as a high school team we had success here," Riley said.

"It's cool coming back to a place that you have some good memories and good familiarity with."

The chasing pack on five under includes South Africa's Christiaan Bezuidenhout and Belgium's Thomas Detry.

Canada's Nick Taylor and South Korea's Kim Seong-hyeon are among a group of four players tied for 10th after shooting four-under-par 68s.

Eleven players are a further shot back on three under after shooting 69, three off the lead.

That group includes Brandon Wu, whose round included a blistering hole-in-one at the par-three fourth hole.

Wu's ace was one of two to light up the opening round. South Africa's M.J. Daffue also snared a hole-in-one en route to a two-under-par 70.

O.Farraj--SF-PST