Fred Funk, 66, shot a 7-under 65 Friday to take the lead after one round of the Ally Challenge in Grand Blanc, Mich.
Funk made his seventh and final birdie on his last hole of the day, the par-4 ninth at Warwick Hills, and lifted a celebratory fist in the air.
It was the first time Funk shot his age or better in PGA Tour Champions competition.
"It was kind of a magical day," Funk said. "Pretty amazing because I haven't had a round in the 60s, I can't even remember when, it's been a long time. I've been playing a little better recently."
Funk said he underwent two back surgeries to get rid of nerve pain, but after several pain-free weeks his body "went into revolt" and locked up on him earlier this week. It improved enough for him to shoot a low score Friday.
"I feel like when I'm feeling good I can still compete," Funk said. "Today was kind of proof of that, at least I validated that thought at least one round."
Woody Austin, Brett Quigley and Canadian Stephen Ames shot rounds of 66 to form a tie for second at 6 under. Scott Parel was alone in fifth at 5-under 67.
Austin won at Warwick Hills in 1995, back when it hosted the Buick Open on the PGA Tour.
A massive 13-player tie at 4-under 68 included Ireland's Padraig Harrington, last week's winner on tour, and Ernie Els of South Africa. Defending champion Joe Durant opened with a 3-under 69.
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