American Gary Woodland rose out of the pack and grabbed a one-stroke lead after the first round of the US PGA Championship.
Woodland erased Rickie Fowler's early-morning lead which looked like it was going to hold up most of the morning, with a six-under-par 64 at Bellerive Country Club on Thursday.
The 34-year-old birdied seven of his last 11 holes to jump ahead of countryman Fowler in St Louis.
Still without a top-10 finish at a major, three-time PGA Tour champion Woodland has set himself up for a career-changing week.
Fowler – wearing yellow in tribute of Australian golfer Jarrod Lyle who passed away on Wednesday following an ongoing battle with cancer – took the early lead with a five-under 65.
He found his best form late, birdieing five of his last 11 holes. With the course playing soft early in the morning, Fowler was able to roll in four birdies on the tough front nine.
South African Brandon Stone, who enjoyed a breakthrough victory at the Scottish Open earlier this year, shot a 66 to sit third alongside two-time major winner Zach Johnson.
World number one and American star Dustin Johnson led a host of players tied at three under heading into the second round.
Johnson reached five under at one point, but two late bogeys derailed his momentum as he closed out the round in a share of fifth with Jason Day, world number three Justin Rose, Ian Poulter and Kevin Kisner among others.
Hideki Matsuyama, Kyle Stanley and reigning Open Championship winner Francesco Molinari were a shot further back.
Defending champion Justin Thomas, Brooks Koepka and Tommy Fleetwood headlined a group at one under.
World number two Thomas won last week's WGC-Bridgestone Invitational and he looked in good form, aside from a late wobble which resulted in two bogeys on the back nine.
Four-time champion Tiger Woods shot an even-par 70 after recovering from a shaky start.
Woods started his day with a bogey and a double-bogey, but regrouped to remain in the mix – playing his last 10 holes bogey free at three under.
Four-time major winner Rory McIlroy, who played alongside Woods, also shot a 70.
Seeking a career Grand Slam of majors, Jordan Spieth posted a one-over-par 71 to open his bid.
|Balotelli staying at Nice|
|It wasn´t a penalty, says Hodgson as Palace boss fumes at refereeing decisions|
|Salah can play much better - Klopp demands more from Liverpool star|
|Gasly to Red Bull: Vettel, Verstappen and the drivers who took their Toro Rosso chance|
|Klopp in the dark on Karius future amid links to Besiktas|
|Simeone pleased with draw after rigours of Super Cup|
|Captain Reus saves Dortmund in DFB-Pokal|
|I couldn´t care less - Klopp rejects title challenge talk|
|Ailing Bairstow keen to aid England´s unlikely victory bid at Trent Bridge|
|Redskins secure Peterson signing|
|Manchester City goalkeeper Bravo suffers ruptured Achilles|
|Crystal Palace 0 Liverpool 2: Milner and Mane secure victory at Selhurst Park|
|Whyte takes aim at ´coward´ Fury ahead of Wilder showdown|
|Jets delighted with Darnold, open to trading Bridgewater|
|Gasly to replace Ricciardo at Red Bull|
|Valencia 1 Atletico Madrid 1: Rodrigo strikes to deny Simeone´s side|
|Injured Halep withdraws from Connecticut Open|
|Cipriani fined £2,000 by Gloucester|
|Mourinho will be sacked before Christmas, says Sharpe|
|England face record chase after Kohli smashes India to huge lead|
|Ozil captaining Arsenal a miracle - Hoeness|
|Japan players apologise for ´thoughtless, careless´ actions at Asian Games|
|Henry wants Bordeaux job, Wenger confirms|
|Pogba too inconsistent and not a leader, claims Scholes|
|PCB chairman Sethi resigns in letter to Pakistan prime minister Imran Khan|
|US Open comes too soon for Tsonga|
|Unpredictable results making 2018 F1 season a classic - Wolff|
|Mendy restricts phone use on Guardiola advice|
|Modric brands Inter approach claim ´the greatest nonsense in history´|
|Runners and Ryders: Olesen leapfrogs Poulter into last Team Europe berth|
|Kenedy escapes further action over Camarasa kick|
|England´s Bairstow suffers ´small fracture´ to finger|
|Gonalons joins Sevilla on loan from Roma|
|Modric, Ronaldo and Salah final UEFA Player of the Year nominees|
|Tottenham to play opening Champions League home match at Wembley|
|Karius´ Champions League blunders did not lead to Alisson signing - Klopp|
|Leeds considered €20m Conte offer before turning to Bielsa|
|Modric, Rakitic lead new era for World Cup finalists Croatia|
|Storm´s Chambers banned for three weeks, Smith injury not serious|
|Porte to race Vuelta after recovering from Tour crash|
|The Career Golden Masters: A run-down of Djokovic´s magnificent record|
|Japan send home four basketball players from Asian Games amid prostitution scandal|
|Rugby tackle bags helping Liverpool´s Alisson with Premier League life|
|Federer raring to go at US Open after Djokovic defeat|
|Chelsea boss Sarri plans to give up smoking|
|Alonso´s Toyota team stripped of Silverstone victory|
|Ceballos: No issue with former Real Madrid boss Zidane|
|MLS Review: Martinez equals single-season goalscoring record|
|Astros avoid sweep with win over Athletics|
|Seppi advances, Paire exits Winston-Salem|
|Bale feeling good as Madrid eye sweep of trophies|
|You can´t leave a house three-quarters built – Neville urges United to back Mourinho|
|Dodgers slugger Machado leaves game after being struck by pitch|
|Harden says Carmelo will ´be a good fit´ for Rockets|
|Morata: I never considered Chelsea exit|
|Gavrilova kicks off title defence in New Haven|
|Lopetegui pleased with Bale and Real Madrid after LaLiga opener|
|It´s a very special moment – Djokovic revels in Golden Masters achievement|
|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|
|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|