Jordan Spieth rued a "brain fart" at the 15th hole that halted the momentum he had garnered during round one of his Open Championship defence.
The three-time major winner was going nicely at three under through 14 holes, but a six iron into a fairway bunker meant his third shot had to be played out to the left and eventually cost him a double bogey.
Further wayward striking led to dropped shots at the 16th and 18th holes as Spieth signed for a one-over-par 72, which was six shots back of clubhouse leader Kevin Kisner.
And the American acknowledged his opening round was a missed opportunity to be further up the leaderboard.
"It was an easy decision. I just hit the wrong club [at 15]," he said.
"I hit a four iron off the tee. I thought it was locked up and it ended up in the fescue.
"I hit a lot of shots I didn't think were as good and I walked up and kind of got good breaks, especially starting the round.
"But the problem was on the second shot I should have hit enough club to reach the front of the green and even if it goes 20 yards over the green, it's an easy up-and-down.
"And that's what I would consider as significant advantage for me is recognising where the misses are, and I just had a brain fart, and I missed it into the location where the only pot bunker where I could actually get in trouble, and it plugged deep into it.
"It was a really, really poor decision on the second shot and that cost me.
"It felt like a missed opportunity. I felt like I was really going well. I had a nice par save after driving it in the bunker at six.
"Other than that, it was very stress-free. I was putting the ball where I needed to, having maybe no more than fewer feet for par on every hole. It was just a clean round of golf."
Despite his disappointing finish, Spieth is confident he can claw his way back into contention for the Claret Jug.
"I think I'm certainly in a recoverable situation. I mean, I imagine this is as easy as the course could play," he added.
"I don't see the winning score being any better than it was in 2007 with [Friday's] forecasted tough conditions and Sunday's forecasted heavy winds.
"It's not a bad place to be. You know, a solid round to stay in the top 25, top 20 will be kind of the goal to feel like I can do something on the weekend."
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