(CNN) โ It was only last month that Rory McIlroy and Bryson DeChambeau were dueling for the US Open in the North Carolina sun. Yet, as the duo lumbered around a damp and windy Royal Troon on Thursday, that high-octane shootout might as well have taken place a lifetime ago.
Reigning US Open champion DeChambeau and runner-up McIlroy slogged to slow starts at the 152nd Open Championship in Scotland, carding opening rounds of five-over 76 and 78 respectively to plummet away from the early leaders.
Out to exorcise the demons of yet another heartbreaking major near-miss at Pinehurst No. 2, Northern Irelandโs McIlroy was even-par through his first seven holes before his day began to unravel at the iconic โPostage Stampโ eighth.

The world No. 2 winced in agony as his ball โ which looked to have settled on the green of the 118-yard par-three โ cruelly trickled into a nearby bunker. It took McIlroy two attempts to escape the sand, his exasperation compounded when his putt for bogey trickled inches past the cup.
That double bogey was followed up by yet another at the par-four 11th, kickstarted by an out of bounds drive that sailed onto the train tracks running down the right side of the fairway.
Forced to take a drop from the tee, McIlroy tapped in for six before more bunker trouble saw him add two more bogeys at the 15th and final holes.
โThe course was playing tough,โ the 35-year-old told reporters. โThe conditions are very difficult in a wind that we havenโt seen so far this week โฆ one of those days where I just didnโt adapt well enough to the conditions.โ
It was another bitter day for McIlroy, who had looked on track to end his 10-year wait for a fifth major title at the US Open before he missed two putts from inside four feet across the last two holes to fall one shot shy of DeChambeau.
McIlroy โ who had made his previous 496 putts from within three feet โ was left inconsolable, speeding away in his car almost immediately after his American rival tapped in for victory before announcing he would be taking a few weeks away from the game to process โprobably the toughestโ day of his 17-year professional career.
The 26-time PGA Tour winner returned with a tied-fourth finish at last weekโs Scottish Open in a strong warm-up for his pursuit of a second Open title, but now faces an uphill battle just to make the weekend, let alone add to the Claret Jug he won at Royal Liverpool in 2014.
โYour misses get punished a lot more this week than last week or even, geez, any week,โ McIlroy said.
โAll I need to focus on is tomorrow and try to make the cut. Thatโs all I can focus on.โ
DeChambeau: โI could have thrown in the towelโ
DeChambeau faired only slightly better as he began his chase of a second consecutive major crown, leaving the American to lament the wet weather and his own equipment.
A double bogey at par-five sixth hole โ the longest in championship history at 620 yards โ proved the lowlight of the LIV Golf starโs round. Having sparked his tee drive into the native area, DeChambeauโs follow-up effort dribbled only a few feet before his subsequent shot careened onto an entirely different fairway.
The 30-year-old was seven-over after another bogey at the 15th hole, but was soon fist-pumping โ a celebration that had been a staple of his crowd-wooing US Open win โ after lasering a stunning 54-foot eagle putt into the 16th cup.
Two closing pars consolidated a strong finish, leaving DeChambeau to rue a sluggish start.
โIโm just proud of the way I persevered today,โ he told reporters.
โShoot, man, I could have thrown in the towel after nine and could have been like, โIโm going home.โ But no, Iโve got a chance tomorrow. Iโm excited for the challenge.โ
Nicknamed โThe Scientistโ for his analytical approach to the game and willingness to experiment with new technologies, big-hitting DeChambeau said โequipment-relatedโ issues had compounded his difficulty in adjusting to playing in the rain.
โIn colder, firmer conditions the golf ball is not compressing as much, so itโs probably something along those lines,โ he added.
โFelt like I was swinging it somewhat okay, just the ball wasnโt coming off in that window that I normally see, so it was a weird day โฆ If I have some putts go in and hit some shots the way I know how to and figure out this equipment stuff, Iโll be good.โ
DeChambeau trailed Justin Thomas by eight shots when his compatriot returned to the clubhouse having opened with an impressive three-under 68.
Thomas has struggled for form since capturing his second PGA Championship in 2022, missing the cut in five of his subsequent nine major outings, but looked like his former world No. 1 self as he poured in seven birdies.
โI just want to just keep playing as good as I can,โ the world No. 29 told reporters.
โI feel like everything has been turning the right way, and Iโve been working on the right things, just havenโt really had much to show for it. Thatโs just how this game works sometimes.โ
The-CNN-Wire
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