The performance was good for a one-shot advantage over second-round co-leader William McGirt, who cruised to his second straight 66 to finish 54 holes at minus-15.
Scott Piercy, who also held a share of the lead coming into Saturday, carded his second consecutive 67, falling into sole possession of third place at 14-under 196.
Sharing fourth at minus-12 were Scott Stallings and Chris Kirk -- each of whom registered 7-under 63s -- and Bo Van Pelt (67).
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