Funk finished the round with a 5-under-par 67 at The Woodlands Country Club. That was good enough to wind up at 14-under 202 and claim the victory, the seventh of his Champions Tour career and first since 2010.
Lehman settled for pars on the final four holes, carding a 4-under 68 and ending one behind Funk at minus-13.
Mike Goodes took sole possession of third place three shots further back with a 2-under 70.
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