Langer got off to a quick start with birdies on four of the first six holes and added two more in the late going at the TwinEagles Club to forge a one-shot lead.
Bob Tway held sole possession of second place with a 7-under 65.
Olin Browne finished 18 holes one stroke further back at minus-6.
Sharing fourth place at 5-under 67 were Kirk Triplett and Duffy Waldorf.
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