Atwal ended his campaign with a total of one-under 279 after fetching two birdies against an equal number of bogeys and a double bogey.
The Orlando-based golfer was off to an ominous start as he stumbled to a bogey on the first hole and a double bogey on the sixth hole compounded his woes as he made the turn three-over.
The back-nine turned out to be slightly better as Atwal picked up birdies on the 11th and 18th hole but a bogey sandwiched in between left two-over for the day.
American Bubba Watson (66) clinched the title after beating compatriots Corey Pavin (66) and Scott Verplank (64) in a play-off.
All three golfers finished with totals of 14-under 266 but Watson emerged triumphant in the play-off.