Former champion Robert Streb matched his career low to claim a two-shot lead after two rounds at The RSM Classic.

Streb carded a nine-under-par 63 to top the leaderboard at the halfway stage of the PGA Tour tournament on St Simons Island on Friday.

The 33-year-old, whose lone Tour triumph came via the 2014 RSM Classic when it was known as the McGladrey Classic, birdied his last two holes on the Plantation Course at Sea Island.

Streb, bogey-free with nine birdies, led by as many as five strokes before ending the second day two shots clear of joint-overnight leader Camilo Villegas on 14 under.

The last four winners of The RSM Classic – Tyler Duncan, Charles Howell III, Austin Cook and Mackenzie Hughes – each held the 36-hole lead.

"I don't want to be the one that breaks it," Streb said. "There's still a lot of golf left, and we'll see what happens."

Villegas followed up his first-round 64 with a six-under-par 66, highlighted by an eagle at the last, as the Colombian eyes his fifth Tour crown and first since 2014.

He carded his lowest opening 36-hole score of his Tour career this week.

Bronson Burgoon (63) and Patton Kizzire (66) are tied for third, three shots off the pace heading into the weekend.

Including his second-round 70, Peter Malnati is now a collective 60 under through his first 20 rounds of the season, with only two over-par scores. By comparison, in his final 20 stroke-play rounds last season, he was five over with nine over-par scores.

Malnati is among 11 players tied for 11th position, including Matt Wallace (71), who went from co-leader to seven shots adrift of Streb.

Former world number one Jason Day (67) is a stroke further back, while Justin Rose (70) and defending champion Duncan (66) missed the cut.