Former US Open champion Gary Woodland headlined a leading trio at Quail Hollow on Friday, where two-time winner Rory McIlroy was in the mix along with five-time major champion Phil Mickelson.
Woodland, the 2019 US Open winner who has struggled of late, carded a two-under-par 69 for a six-under total of 136, where he was joined by England's Matt Wallace and American Patrick Rodgers.
Wallace, a four-time European Tour winner who is gunning for a first US tour title, had five birdies in his four-under 67 while Rodgers posted a 68 highlighted by a 13-foot eagle putt at the seventh.
The three were one stroke in front of Kramer Hickock, who posted a 69 for 137.
McIlroy, who was outside the projected cutline after a first-round 72, grabbed six birdies in a five-under-par 66 to head a group on four-under 138 - just two shots off the lead.
Mickelson, who held the overnight lead after a sparkling seven-under 64, was 11 shots worse in the second round, but his four-over 75 left him in a group only three strokes off the pace on three-under 139.
Woodland, who said his missed cut at Innisbrook last week marked the "rock bottom" of a downward trend that all started with a left hip injury and his attempt to play through pain, said a phone consultation with coach Butch Harmon and in-person work with Pete Cowen had helped him start to get back to what he was doing "when I was hitting it well."
"I've seen some shots this week that I just haven't seen in a long time," Woodland said. "The golf swing feels so much better. Confidence has gone way up, which I did not have really in the last year."
Wallace, meanwhile, thinks he's trending toward a first US title, after a third-place finish at the Texas Open last month.
"I'm on a nice run of form and this is where you want to be in golf, trying to win big tournaments," he said.
Former world number one McIlroy, meanwhile, is headed to the weekend for the first time in four starts, having missed the cut at the Players Championship, failing to reach the weekend at the WGC Match Play, and missing the cut at the Masters.
The Northern Ireland star hit just five fairways but found 14 of 18 greens.
"I felt like I found something with my iron play last week. I didn't get a chance to show it yesterday because I wasn't finding the fairway much. But having some more opportunities today, I was able to show it a bit and it was nice.
"I played some really good shots into the par-threes and that's something that I haven't been doing for the last few months, so that was nice."
Mickelson's four-over 75 included two balls in the water, including his tee shot at the par-three 17th that led to a double-bogey and, he said, epitomised his recent troubles maintaining focus.
"I think kind of an example of what I've been talking about is like on 17 we're standing over the ball and I'm changing my mind and I'm changing the shot, moving the clubhead a little bit ... instead of backing away and kind of refocusing, I just kind of hit it and I'm not really kind of aware of what I'm doing," Mickelson said.
Leading second-round scores on Friday in the PGA Tour Wells Fargo Championship at Quail Hollow in Charlotte, North Carolina (USA unless noted, par-71):
136 - Matt Wallace (ENG) 69-67, Gary Woodland 67-69, Patrick Rodgers 68-68
137 - Kramer Hickok 68-69
138 - Scott Piercy 70-68, Rory McIlroy (NIR) 72-66, Keith Mitchell 67-71, Carlos Ortiz (MEX) 70-68, Scott Stallings 69-69
139 - Luke List 67-72, Phil Mickelson 64-75, Bubba Watson 70-69, Abraham Ancer (MEX) 69-70
140 - Joel Dahmen 68-72, Stewart Cink 71-69, Patrick Reed 71-69, Matt Jones (AUS) 69-71, Ben Martin 69-71, Emiliano Grillo (MEX) 74-66, Roger Sloan (CAN) 76-64, Brian Harman 68-72, Satoshi Kodaira (JPN) 68-72, Vincent Whaley 72-68