KENTUCKY (AFP) — Trevor Cone, a rookie with only 20 prior US PGA Tour starts, fired a nine-under par 63 to grab a one-stroke lead after Saturday's third round of the Barbasol Championship.

The 30-year-old American made nine birdies in a bogey-free round to stand on 17-under par 199 after 54 holes at Keene Trace Golf Club in Nicholasville, Kentucky.

He was one stroke in front of 2009 US Open champion Lucas Glover and Sweden's Vincent Norrman.

World No. 450 Cone, whose best PGA finish was a share of 23rd at the Byron Nelson in May, shot his low PGA round by two strokes, with birdies on three of the first four holes and three of the last five.

"I hit it really well, hit it pretty close early on and then made a couple of 10- to 15-footers on two, three and four," said Cone, who sank a 10-foot birdie putt at the par-three second, another from just inside 10 feet at the third and one from just outside 14 feet at the fourth.

He birdied from just outside five feet at the sixth and just beyond six feet at the par-5 eighth.

After missing the green at the par-3 ninth, Cone salvaged par by sinking a 14-foot putt, boosting momentum for the back nine.

Cone reached the green in two at the par-5 11th for a tap-in birdie, then added birdie putts of four feet at the par-3 14th and drove the green in two at the par-5 15th to set up a tap-in birdie.

He closed with seven-foot putts to save par at 17 and birdie the 18th to reach the clubhouse with a two-stroke edge.

"Just played smart — fairways, greens, not get too aggressive," Cone said.