Ryuji Imada, winner of last year's Virginia Beach Open, is tied for second place with former PGA Tour veterans Lee Rinker and Mike Heinen. The trio is knotted at minus 10.
Rod Pampling, a co-leader after the second round, shares fifth with Jeff Freeman and Brian Tennyson at 9-under-par.
Patterson birdied the third hole but quickly dropped a shot at the next. He then ran off four birdies in a row, starting at the sixth. This is the second day in a row where Patterson had four-birdie run at the turn, as Patterson carded four in a row beginning at the seventh on Friday to give him a weekend spot in the tournament after a first-round 73.
At the 11th, Patterson nailed a 50-foot birdie putt to go to 9-under. He bogeyed the next hole but closed with three birdies in his last five holes for his 64.
'It's a whole new experience for me,' said Patterson, who is looking to become the first player to win his first event on this tour since Stuart Appleby captured the 1995 Monterrey Open.'
'I'm in unchartered waters. This whole week has been more than I ever would have hoped for.'
Imada and Rinker each combined five birdies and a bogey on Saturday for their respective 67s. Rinker saved par on the sixth after his second shot hit a tree and went backwards. A sand wedge to five feet saved his four. At the eighth, his drive was lodged against a tree and he was forced to hit left-handed with the back of his 5-iron. Rinker holed a 30-footer for the save. Heinen was 1-over after 10 holes but closed with four birdies for a 3-under 68.
Freeman went bogeyless on Saturday with a 6-under 65 while Tennyson used five back-nine birdies for a 66. Pampling traded five birdies with five bogeys for an even-par 71.
Deane Pappas, the other co-leader after round two, birdied the last hole but still struggled to a 1-over 72 on Saturday.
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