CHARLOTTE, N.C. - Webb Simpson has plenty of hometown knowledge when it comes to playing Quail Hollow Club.

He might need every bit of it if he hopes to hold off Rory McIlroy and Phil Mickelson this weekend.

Simpson chipped in twice for birdie and shot a 5-under 67 for a share of the second-round lead with Robert Streb in the Wells Fargo Championship. Streb had a 69 to match Simpson at 10-under 134.

"Playing here quite often, I know where the best places are to miss (the green)," said Simpson, who lives in Charlotte and has played the course countless times.

Simpson knows it will take a lot more big shots over the weekend to win with some of golf's top names lurking behind him.

McIlroy and Mickelson were three shots back. Mickelson had a 66, and McIlroy matched Simpson's 67.

Martin Flores and Patrick Rodgers were tied for third at 8 under.

"I know I have to make birdies," Simpson said.

Mickelson made seven Friday.

One day after joking that he "turned a 66 into a 71" in the opening round with some missed opportunities, Mickelson got his 66.

"Right now nobody is turning 66s into 71s better than me," Mickelson joked, so it's nice to finally shoot that 66 and get the score that reflects the way I feel I'm playing."

Mickelson thought he didn't play all that bad last week, but still missed the cut at The Players Championship. He appears to be back in a big way.

McIlroy was on his game, too.

The world's top-ranked player said his focus Friday was on eliminating mistakes after an up-and-down 70 the day before. He did just that, posting five birdies and no bogeys. He was never in any real danger of making bogey in what he called a "stress-free round."

"Anytime you can play a round of golf with no bogeys you're doing something right," said McIlroy, who won the 2010 event for his first PGA Tour victory.

McIlroy rolled in a 30-foot birdie putt on the first hole to gain some early momentum. He went on to hit 14 of 18 greens in regulation with 29 putts.

With four top-10 finishes in six events this year, McIlroy's confidence keeps growing. He said his biggest strength now is his patience, understanding that he doesn't have to go for every birdie opportunity.

"Just knowing from experience what a good score is and (that) sometimes, if it's just not happening, you're not losing any ground," McIlroy said. "I felt like I could have shot 63 or 64, but realizing that 67 is still a good score and puts me in position going into the weekend."

The biggest surprise high on the leaderboard is the 22-year-old Rodgers, a regular on the Web.com Tour who is playing on a sponsor's exemption. He ranks 333rd in the world and has never finished in the top 25 on the PGA Tour.

That clearly didn't affect his confidence.

Rodgers, who played at Stanford, rents a house with Jordan Spieth in Jupiter, Florida. He plays golf with the Masters champion regularly at The Bear's Club. He said being around one of the best golfer's in the world is making him better.

"The young guys are ready to come out here and win," Rodgers said. "I feel no different. I feel really prepared. That's why I turned professional. I'm excited to get in the mix this weekend."

Flores is in the mix too for the second straight year.

He shared the lead at the midway point of the Wells Fargo Championship last year with Angel Cabrera and turned in a career-best third place finish. He shot 67 on Friday.

"Certain courses kind of fit your eye," Flores said. "This is one of them."

Simpson's eye was just fine, too.

He chipped in on the par-4 ninth hole from the right side of the green, then duplicated the feat on the difficult par-3 17th hole to move into a tie for the lead when Streb stumbled on No. 16 and recorded his only bogey of the tournament.

But the shot of the day belonged to Colt Knost, who had a hole-in-one on the difficult 227-yard 17th hole. Knost knocked his tee shot over the water and it rolled 30 feet to the hole, hitting the flag stick and fell in.

He grabbed the ball out of the cup, turned and lobbed it into the cheering gallery.

He was right on the cut line, but the eagle there and a birdie on the 18th earned him an opportunity to stick around for the weekend.

The tournament was not so kind to some former Wells Fargo champions as J.B. Holmes, Jim Furyk, Vijay Singh and Derek Ernst all failed to make the cut.