The 44-year-old fired a closing 3 under 69 at the low-scoring Keene Trace Golf Club in Nicholasville to end the week in a share of 7th place at 19 under.
Percy, who has only limited status on the PGA Tour in 2018 and mixes events between the Web.Com and PGA Tours, was playing his 10th event of the year on the main tour and was in contention early on, tied for 2nd place through 36 holes.
But the 20-year professional was unable to sustain that same pace over the final 36 holes which carried over until Monday US time.
Percy's best ever finish on the PGA Tour came in Las Vegas in 2010 when beaten by Jonathan Byrd in a playoff in Las Vegas after Byrd made a miraculous hole-in-one in extra time to win.
Percy continues to show signs of significant improvement with his strong week in Kentucky complimenting a 6th place finish at a Web.Com Tour event last month.
In this interview recorded after round two of the Barbasol Championship, he talks about the reason why things have made a turn for the better.
Percy was the only Australian to make the cut in the weather disrupted event which was won by American Troy Merritt at 23 under.
It was Merritt's second PGA Tour title following his first victory at the Quicken Loans event in 2015.
Merritt won by one shot over Billy Horschel, Richy Werenski and Tom Loveday in the event which ran opposite the Open Championship.
KIERAN PRATT: TOURNAMENT PUTTING WARM-UP
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