Danny Lee has blown a chance of a strong finish in the opening PGA Tour playoff event in Boston.
Lee started the final day of the Northern Trust event in a tie for fifth and even moved up to third after a four-under start in the first nine holes, but capitulated in the back nine to fall down the leaderboard to 18th.
The 30-year-old Kiwi had a shocking six bogeys on the back nine, including five successive bogeys, to card a two-over 73 to finish 12-under for the tournament.
Runaway leader Dustin Johnson finished 11 shots ahead at 30-under.
Lee's poor finish sees him drop to 42nd on the FedEx Cup standings, leaving him with some work to do at the BMW Championship if he wants to make the season-ending Tour Championship – the richest tournament in golf – where the top 30 in the standings qualify.