Seamus Power remained 142nd in the FedEx Cup standings when he bogeyed two of his last three holes and closed with a costly three-over 73 in the Quicken Loans National in Maryland.
The 30-year old from West Waterford went into the final round tied for 18th but finished up tied for 38th after a round featuring four bogeys and a chip-in birdie at the par-five 10th at the TPC Potomac at Avenel Farms.
Power had a good week from tee to green (he was ranked 10th) but he was 71st for strokes gained putting and paid the price, despite earning $30,530.
He is 176th for final round scoring with a stroke average of 72.25 compared to 69.39 in round one (7th), 69.94 in round two (T20) and 71.15 in round three (123rd).
Former Walker Cup player Kyle Stanley captured the title when he beat Charles Howell III with a par at the first extra hole.
Stanley and Howell closed with a four-under 66s to finish one stroke ahead of Rickie Fowler and Martin Laird on seven-under par as overnight leader David Lingmerth shot 73 to finish tied for fifth, three shots outside the playoff.
It was Stanley's first win since 2012 while Howell (who has won $33m on tour) has won only twice since joining the PGA Tour in 2000.
Howell had an 18 footer for the win on the 18th and a 10 footer for par to stay alive in sudden-death, now has 16 runner-up finishes to his credit with his last victory coming more than a decade ago in the Northern Trust Open at Riviera.
It was still a laudable effort in his first start in 10 weeks after suffering a rib injury.
“Going into this week I was extremely rusty,” he said. “I can’t believe how well I’ve played.”
Stanley made a five-footer for the win and failed to hold back the tears afterwards.
A Walker Cup player alongside the likes of Fowler, Dustin Johnson and Webb Simpson at Royal County Down in 2007, he earned more than $1.5 million in his rookie season on the PGA Tour in 2011 and won the Waste Management Phoenix Open in 2012.
He then suffered a slump and was forced to split time between the PGA Tour and the Web.com Tour in 2015 before rebounding.