Garcia was 4-under-par in the final round for a 72-hole total of 18-under 262. He finished two strokes ahead of Tim Clark and was three up on Bud Cauley.
Rain limited play Sunday, when the tournament was to have finished, and Garcia, who had the lead after three rounds, got in just four holes of his fourth round Sunday.
He opened play Monday with six consecutive pars but he had birdies at Nos. 11 and 13 around a bogey at 12. He pulled away with consecutive birdies over 15-17 and survived a final-hole bogey for a final round of 66.
Garcia hadn't won a PGA Tour event since the Players Championship in May 2008. He did have a pair of wins last year on the European Tour. He owns eight PGA titles and 23 championships overall.
Clark had a 67 in the final round and was 16-under for the tournament. Cauley, with a fourth-round 68 for a 72-hole total of 265 was third. Chad Campbell (66), Jimmy Walker (67) and Carl Pettersson (68) tied for fourth, four strokes behind Garcia.
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