Jhonattan Vegas became the latest player to shoot 62 on the PGA Tour.
Vegas poured in nine birdies in a bogey-free round to vault into the lead during the second round of the John Deere Classic. It is the sixth consecutive round on Tour a player has fired 62.
"Probably the best I've felt all year, to be honest," Vegas said. "I hit the ball extremely well, kind of what I've been struggling with a little bit the past few months."
The 34-year-old is at 13-under par at the halfway point, holding a three-shot cushion over Harold Varner III and Russell Henley.
Vegas, who opened with a 4-under 67 on Thursday, had seven birdies in a 10-hole stretch (Nos. 13-4). He chipped in from 20 feet for par at the par-4 fifth.
In his first event since the U.S. Open, Vegas hit 16 of 18 greens.
Varner had a second-round 65, including an eagle at the par-4 14th.
"It's nice when you're playing well to be in contention," Varner said. "Just got to keep doing what I'm doing. I feel like I'm doing a lot of things well.
"I love playing golf, and I love being here. I've played well here, so it's good to be back."
Henley had the lead for much of the morning, but made a double-bogey at the par-4 18th.
"I didn't hit it quite as well today," he said. "A couple mistakes there on 18, but I feel confident in my game. I haven't made a cut in a while, so it's been a grind. I'm just trying to hang in there, a long way to go."
First-round leader Roberto Diaz, who had 62 Thursday, struggled in the second round. He was 1-over after 16 holes and 8-under for the tournament.
Zach Johnson was hovering around the cut line. Johnson, who had streak of 41 consecutive rounds at par or better end Thursday, rebounded with a 4-under 67. He was in at 3-under par for 36 holes.