David Howell admitted to being "fed up" after he lost a three-shot lead over the last four holes at the US Open.
Howell was left to rue his nine putts over the last four holes
The 30-year-old carded six birdies over 10 holes to get to four under, three clear of Colin Montgomerie's target.
But the Englishman then bogeyed the 15th and 16th before closing out with a three-putt double-bogey at the last.
"Once I calm down a bit, it's still level par and it's a great round of golf," he said afterwards. "Right now, I'm frustrated and I'm fed up."
But Howell, the European Order of Merit leader, will be dismayed at how quickly the Winged Foot course clawed back shots he had picked up in his mid-round purple patch, particularly as the wind had dropped and conditions were at their best.
"It's such a shame to drop shots in the easiest part of the day," he said. "But if you hit bad shots around here, you're going to get punished, no matter what wind there is."
Howell, however, should be proud of the way he bounced back from carding two bogeys in his first four holes.
I hit plenty of good shots, so let's not dwell on the bad ones
He should also remember that no other player got lower than two under par at any stage during a tough first round at the New York course.
"I was delighted to get to four under and I hope I see it again," said Howell, by now trying to put a positive spin on his day's efforts.
"It's the best I've played in a US Open by a long way."
The Swindon-born golfer, in fact, has a pretty unremarkable record in majors, certainly one beneath his current status as the ninth best player in the world.
But he has already claimed two big wins on the European Tour this season, beating Tiger Woods down the stretch in Shanghai in November and claiming the tour's flagship event at Wentworth last month.
And having overcome the injury problems that have held him back over the last 12 months - he was forced to withdraw from the US Open last year after pulling a muscle on the driving range - the 2004 Ryder Cup star is ready to add to the two top-20 finishes he has picked up at the Masters.
"I'm in great shape," he said. "I would rather be three under but I'm not. I hit plenty of good shots, so let's not dwell on the bad ones."