Defending champion Zach Johnson and Camilo Villegas each carded 7-under 64s on Thursday to share the lead after the opening round of the John Deere Classic.
Matt Bettencourt, Daniel Summerhays and Brendon de Jonge shot matching 6-under 65s at TPC Deere Run to share third place, while Colonial winner Boo Weekley is among a group of seven players tied for sixth at 5-under.
Weekley is joined by Jim Herman, Matt Jones, David Hearn, Vaughn Taylor, Kevin Streelman and Robert Streb.
Steve Stricker, who had his three-year winning streak at this event snapped by Johnson last year, shares 13th place with 12 other players at 4-under.
Johnson was the first of the co-leaders to hit the course and he started on the back nine.
After getting on the board with a birdie at the 11th, he moved to 2-under with a 22-foot birdie putt at the 15th.
He followed that with a 10-foot birdie effort at the 17th to make the turn at 3-under and opened his inward nine with a pair of gains at the first and second.
He then rolled in another putt from beyond 20 feet at the fifth to start another set of back-to-back birdies and reach 7-under. He closed his bogey- free round with three straight pars to remain there.
"I have always felt comfortable here, regardless of my numbers," said Johnson, who is from Cedar Rapids, Iowa. "When you are comfortable with the surroundings, when you're comfortable with the peripherals (it helps). My routine has been the same here the last three or four years. We're staying in the same place. I've got my family here. The (John Deere Classic) staff does a great job of just letting me get into my game."
Villegas started on the front nine and he also had the putter working for him as he converted on birdie putts of 14 and 20 feet at the second and fourth, respectively, to reach 2-under.
He traded a birdie at the seventh with a bogey at the ninth to close out his outward 33 before he opened his back nine with three straight gains from the 10th that included a 22-foot putt at the 11th to move to 5-under.
A 13-foot birdie putt at the 14th pulled him within a stroke of the lead, and Villegas was later able to meet Johnson atop the leaderboard with a short birdie effort at the 17th.
Villegas had a chance to grab the outright lead with a lengthy birdie putt at 18th, but he was unable to convert and tapped in for par to maintain his share of the lead.
"Made some great putts and just kept out of trouble," Villegas said about his round. "I was very pleased with the way I handled myself out there. It was a nice, relaxed, chill attitude and I enjoyed every single bit of the round."
Bettencourt, de Jonge and Summerhays all fired bogey-free rounds, with Bettencourt and Summerhays each recording six birdies, while de Jonge posted four birdies and an eagle.
NOTES: Johnson has shot 17 straight rounds in the 60s at TPC Deere Run ... This is the fourth tournament this season Villegas has opened with a 65 or better ... Johnson is looking for his first win since last year's John Deere Classic, while Villegas is seeking his first victory since the 2010 Honda Classic ... Johnson recorded his eighth career bogey-free round at TPC Deere Run, which ties him with Kevin Sutherland for the most in tournament history ,,, Bettencourt was added to the field on Wednesday after Neal Lancaster withdrew.