A quadruple bogey seven at the 17th sent Graeme McDowell crashing outside the top 30 in the Honda Classic.
As Colombian Camilo Villegas impressively claimed his third PGA Tour title by five shots from Anthony Kim at Palm Beach Gardens, McDowell dropped six shots over the last six holes for a 76 that relegated him to tied 31st on two over par.
The Ryder Cup star from Portrush was just a stroke off the lead with 37 holes to play before a series of self-inflicted disasters cost him dear.
His troubles started with the self-imposed two stroke penalty he incurred for grounding his club in a hazard at the 18th on Friday.
That left him three behind Villegas and Kim entering the weekend but it was the Bear Trap that did the rest of the damage.
The holes from the 15th to the 17th cost McDowell eight shots over the final two rounds.
On Saturday the Ulsterman battled like a dog all day but bogeyed the 180 yard 15th after a visit to the water and then doubled the 16th by taking four to get down from greenside sand in an otherwise excellent 71.
Seven strokes behind Villegas starting the day, McDowell still had high hopes of a top 5 finish but his week was ruined by the holes Jack Nicklaus redesigned.
In the final round he was still level par for the day with six holes to play after three birdies and three bogeys.
But he then bogeyed the 13th and 16th before knocking two balls in the water at the 17th to notch a painful seven.
Padraig Harrington shot a level par 70 and Rory McIlroy a one under 69 as they tied for 40th on four over.
Justin Rose shot a sparkling six-under-par 64 in his final round to jump to third place on seven under for the tournament, and fellow Englishman Paul Casey finished a shot behind in a share of fourth place with Fiji’s Vijay Singh.
Villegas dropped three strokes in five holes on the back nine butcfinished in style with a long putt for birdie at the 18th to card a round of 68 for a 13 under total.