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."
20. August 2018
|Sorrentino thanks Ronaldo for support after injury|
|Twins place Santana on DL with finger injury|
|Yankees´ Gregorius suffers ´pretty significant´ heel bruise|
|Snedeker ends PGA Tour drought with Wyndham Championship win|
|Spalletti unconcerned despite Inter´s underwhelming start|
|Djokovic makes history with Masters clean sweep in Cincinnati|
|Real Madrid 2 Getafe 0: Bale gives Lopetegui first LaLiga win|
19. August 2018
|IndyCar driver Wickens taken to hospital after crash|
|Sherman calls for NFL to scrap ´idiotic´ helmet rule|
|Sassuolo 1 Inter 0: New-look Nerazzurri given early reality check|
|Hughton: Shock United win does not alter scale of Brighton´s task|
|Navas keeps place as Courtois waits on Madrid debut|
|Ndidi signs long-term Leicester City contract|
|Pandya tears through feeble England to put India in command|
|Alonso creates motorsport history with victory at Silverstone|
|Kovacic: Chelsea and Sarri believe in me|
|Brighton loss a big lesson for United – Pogba|
|Mistakes hit United´s confidence - Mourinho|
|Brighton and Hove Albion 3 Manchester United 2: Murray lifts Seagulls to another win over Mourinho|
|Quickfire Moon treble sets up Rhinos win|
|Manchester City celebrate win with Silva´s son|
|Brentford 2 Sheffield Wednesday 0: Maupay stars as Bees buzz by Owls|
|Guardiola delighted with fit and firing Aguero|
|Waring marks 200th event with maiden title in Gothenburg|
|Guardiola dismisses Mourinho´s ´disrespectful´ accusation|
|Hulkenberg proud to survive in F1´s pay driver era|
|It´s here, it´s real, get on with it - Dyche dismisses Europa League excuse|
|Grujic agrees Liverpool extension, joins Hertha on loan|
|Martial starts as Lukaku, Young return for Manchester United|
|Fury-Wilder to be staged in November or December - Warren|
|Manchester City 6 Huddersfield Town 1: Aguero hits hat-trick as champions triumph|
|Burnley 1 Watford 3: Hornets end away day woes as Deeney leads destructive display|
|McFarland cleared to leave Scotland and join Ulster|
|Simeone wants ´only the best´ for Filipe Luis amid PSG links|
|PSG signing Boateng rated ´50-50´ by Bayern president|
|Cipriani a positive influence, insists Gloucester head coach|
|Bayer Leverkusen´s Bailey signs contract extension|
|Jesus and Aguero start for City as Mahrez misses out|
|Federer unsure what to expect from Djokovic duel|
|Chievo goalkeeper suffers broken nose, whiplash in Ronaldo collision|
|Simmons lauds influence of ´big brother´ LeBron|
|PSG´s Cavani selected by Uruguay as Coito fills in for Tabarez|
|Starc leads tributes after ´leader of the pack´ Johnson retires|
|Hazard confirms he is staying at Chelsea this month|
|Liverpool´s Firmino dreaming of Premier League title glory|
|Raiders rock the Roosters as NRL´s top-four battle hots up|
|Erasmus demands improved Springboks|
|Athletics pull even with Astros in AL West|
|Mercurial quick Johnson retires from cricket|
|MLS Review: Royer leaves it late for Red Bulls, Dallas bounce back|
|Crotty concussed, Folau injured|
|DFB president Grindel sorry Ozil felt ´deserted´|
|Busch picks up first win of season in Night Race|
|NASCAR results at Bristol: Kurt Busch picks up first win of season in Night Race|
|Woakes welcomes back ´big-game player´ Stokes|
|´Genius´ Messi still amazes Valverde|
|All Blacks, Springboks await Namibia at Rugby World Cup|
|Federer to face Djokovic after Goffin withdraws|
|Rain halts plays at Wyndham Championship|
|De Gea will extend contract soon, says Mourinho|
|Halep to meet Bertens in Cincinnati final|
|Frampton set for Warrington fight after dominant Windsor Park win|
|Messi makes LaLiga history with Barcelona´s 6000th goal|
|MC Alger defeat throws quarter-final chase wide open|
|Barcelona 3 Deportivo Alaves 0: Messi´s milestone goal sets up victory|
18. August 2018
|Djokovic on course for Masters 1000 history after Cilic victory|
|It´s on! - Wilder fight confirmed after Fury defeats Pianeta|
|Like Cruyff before him, Guardiola favouring Foden´s style over substance|
|Ronaldo tweets debut delight after Juve win|
|Chelsea are not title contenders yet, claims Sarri|