TROON, Scotland -- Bryson DeChambeau and Rory McIlroy beat everyone in last month's U.S. Open.
But in the opening round of The Open at Royal Troon Golf Club, they struggled to defeat Mother Nature -- and themselves -- in what was a Thursday morning to forget in the wind and rain on Scotland's west coast.
DeChambeau, who won his second U.S. Open title with a one-shot victory over McIlroy at Pinehurst No. 2, carded a 5-over 76 on Thursday. McIlroy was two strokes worse and trailed first-round leader Daniel Brown by 13 strokes.
DeChambeau vowed to play "boring" golf at Pinehurst, but his game was far from that on Thursday -- for all the wrong reasons. He was 3 over through four holes after a three-putt bogey on No. 1, badly yanking his tee shot on No. 3 for another bogey and then missing a 3-foot par putt on No. 4.
"[The wind] was in and off the right, and I was trying to draw the ball and the ball was knuckling a little bit," DeChambeau said. "It was a really difficult challenge, and I should have just cut the ball."
DeChambeau and McIlroy weren't the only golfers left perplexed by the unpredictable wind at Royal Troon. Golfers typically play the front nine with the wind at their backs, then close with a difficult back nine with the wind in their faces, but it was the opposite in the first round.
On the 620-yard sixth hole, DeChambeau pulled his drive into the native area and hit his second shot just 4 yards out of the high grass. He needed five shots to reach the green, leading to a double-bogey 7. He carded two more bogeys on Nos. 8 and 15 before finally ending the carnage by making a 55-foot eagle putt on the 16th.
"It's a completely different test," DeChambeau said. "I didn't get any practice in it, and I didn't really play much in the rain. Yeah, it's a difficult test out here, something I'm not familiar with. I never grew up playing it, and not to say that that's the reason. I finished eighth at St Andrews [at the 2022 Open]. I can do it when it's warm and not windy."
McIlroy didn't seem to be in trouble on the front nine. He made a bogey on No. 1, but quickly answered with a birdie on the par-4 third. He was even par after seven holes.
On the famous par-3 eighth hole, known as Postage Stamp, McIlroy hit his tee shot into a greenside bunker. He didn't get out the ball on his second shot, leading to a double-bogey 5.
"[It was a] difficult day," McIlroy said. "I felt like I did OK for the first part of the round and then missed the green at the Postage Stamp there and left it in and made a double. But still, I felt like I was in reasonable enough shape being a couple over through 9, thinking that I could maybe get those couple shots back, try to shoot even par, something like that."
Things only got worse for McIlroy after he made the turn. After making a bogey on No. 10, the four-time major champion sliced his tee shot over the railway and out of bounds on the right. That led to another double-bogey that moved him to 5 over.
"Even though the wind on the back nine was helping, it was a lot off the left," McIlroy said. "I was actually surprised how difficult I felt like the back nine played. I thought we were going to get it a little bit easier than we did. The course was playing tough. The conditions are very difficult in a wind that we haven't seen so far this week."
Brown finished with six birdies in a bogey-free round and has a one-shot lead over Shane Lowry.
Justin Thomas, who doesn't have a great track record on links courses and has struggled with his form for much of the past two seasons, grabbed the early clubhouse lead by posting a 3-under 68 in the morning wave.
Thomas chipped in from off the green for a birdie on the par-4 second and added three more birdies and one bogey to make the turn at 3-under 33. After another birdie on the 10th, he badly pulled his tee shot to the left on No. 12 and had to take a penalty drop, leading to a double-bogey. He made a bogey on the 13th after pushing his drive into high rough on the right.
"I just had not played that front nine into the wind before, and that was wild," Thomas said. "I remember trying to drive 1 and 3 in 2016, and I hit 7-iron into 1 today, and I hit a 3-wood up there on 3 to have wedge in. But it just was very, very different. But it just was all very typical of an Open, just trying to make the best out of the conditions that you have."
Thomas closed with birdies on the final two holes, including a 25-footer on No. 18, to get back to 3 under, 1 in front of Alex Noren, Nicolai Hojgaard, Justin Rose and Russell Henley.
Thomas loves playing on links courses but hasn't had much to show for it. He had one top-15 finish in seven previous starts at The Open. At last year's Open Championship at Royal Liverpool in England, he opened with an 11-over 82.
Thomas had the first-round lead at last week's Genesis Scottish Open before finishing in a tie for 62nd.
"I feel like everything has been turning the right way, and I've been working on the right things," Thomas said. "Just like I said, I haven't really had much to show for it. That's just how this game works sometimes. But I know that I'm close the way it is, and I'm just going to keep playing and not play for results, just play for my game, and it'll take care of itself."