Darren Clarke admitted that greed had cost him victory in the MCI Heritage in South Carolina.
Clarke went all out for a birdie on the final hole but a double-bogey on the par-four, his third of the day, allowed Peter Lonard to capture the winning prize money of just under £500,000 (€731,600).
The Northern ace said: “I was probably a little greedy on 18 with the way that I had been swinging all day.
“Fighting left and trying to take an eight-iron in and take down the flag proved to be foolish.”
Clarke and Lonard were tied at seven under going to the 18th and both hit the middle of the fairway with their tee shots.
Lonard found the green on his approach but Clarke’s second shot landed in the deep rough, leading to a penalty stroke.
It was a nightmare finish for Clarke, who held a commanding six-shot lead at 12 under earlier in the tournament.
He stumbled to a 73 on day three and 76 in the final round to finish tied for second at five under with Davis Love III, Billy Andrade and Jim Furyk.