Kelly Kraft, seeking a first US PGA Tour title, fired a seven-under par 63 on Friday to take a one-shot lead over Anirban Lahiri and Webb Simpson at the Greenbrier Classic.
India's Lahiri had set an early target with a nine-under par 61 on the mountain resort course in White Sulphur Springs, West Virginia.
That propelled the 31-year-old world number 99 into a tie with 2012 US Open champion Simpson, who followed his first-round 61 with a 67.
Kraft overhauled them both with a round that included eight birdies and headed into the weekend with a 13-under total of 127.
"I made a lot of putts out there," said Kraft, who drained birdie putts of 27 and 21 feet as well as converting plenty of mid-range efforts. "Anytime you shoot 63 I guess you have to."
Kraft, whose best career finish on the PGA Tour is a tie for second at the John Deere Classic in 2017, had missed the cut in seven of his last 10 events, including last week's National.
"I've kind of changed my attitude, starting with last week," Kraft said. "I felt like I played good last week, it was just a couple breaks here and there. Missing a cut is easy to do out here. But I've changed a couple things in my attitude and I just feel like I'm ready to keep playing good."
Lahiri, also seeking a first PGA Tour win, is coming off two of his best finishes of the season the past two weeks, ninth at the Travelers Championship and 13th at the Quicken Loans National.
"I've been feeling good the last two weeks. I've seen the improvement on the golf course," Lahiri said. "More than anything else, I haven't dropped a shot (this week)."
He began on the back nine with three birdies in a row, the first from 15 feet, the second from 12 and the third from 19 feet at the par-5 12th. At 14 he blasted out of a fairway bunker to 14 feet and sank another long birdie putt.
Lahiri ran off another birdie treble starting at the second after dropping his approach inches from the cup. He sank an 18-foot birdie putt at the par-3 third and a 22-footer to birdie the fourth.
Closing with back-to-back birdies completed his run to the top.
"I'm just happy with the way I'm playing," Lahiri said. "I need to keep grinding. You can really be aggressive on the greens. If I keep myself in play I like the way the golf course sets up."
Simpson battled back after a double bogey on his third hole of the day, the par-five 12th -- which he eagled Thursday.
"It was not the start I was looking for," he said. "But I hung in there."
"I'm just happy with the way I'm playing," said India's Anirban Lahiri, the world number 99 golfer, adding that he needs to "keep grinding" away