Curtis, who last won six years ago at the 84 Lumber Classic, survived challenges from Matt Every and John Huh to finish with a two-shot win at 9-under 279.
Every's putter abandoned him on the back nine and he had to settle for a 1-under 71, good for a second-place tie with Huh (69) at minus-7.
Every was seeking his second crown of the year after earlier taking the Mayakoba Golf Classic.
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