Tim Herron matched the tournament record with a 61 but was still seven strokes back.
Play was halted for 1 hour, 17 minutes late in the day when a system of thunderstorms passed through the central North Carolina Triad.
Walker, who began the day four strokes back, had eight birdies in compiling one of the best two-day scores in event history. Only Pettersson at 125 in 2008 was better than Walker through 36 holes at Sedgefield Country Club.
Bernhard Langer topped the leaderboard at 7 under when first-round play in the Dick's Sporting Goods Open was suspended because of rain Friday in Endicott, N.Y.
Coming off a victory two weeks ago in the 3M Championship, Langer was facing an 8-foot birdie putt on the 16th hole when play was stopped.
"I played pretty solid. I drove the ball very well. I hit a lot of fairways to give myself opportunities with my iron shots," said Langer, who closed with a 62 in his victory in Minnesota. "I'm disappointed we had to stop because I was going well, feeling good, but hopefully we'll continue tomorrow."
Mika Miyazato and Sydnee Michaels shot 7-under 65 on Friday in 100-degree heat to share the first-round lead in the LPGA Tour's Safeway Classic in North Plains, Ore.
Miyazato and Michaels each had eight birdies and a bogey on Pumpkin Ridge's Ghost Creek Course.
Cristie Kerr, Inbee Park and Pornanong Phatlum were a stroke back. So Yeon Ryu, the Toledo Classic winner last week, was two shots behind at 67 along with Brittany Lincicome, Alison Walshe and Jee Young Lee.
Jimmy Walker -12
Webb Simpson -11
4 tied at -10
Daniel Summerhays +2