A dejected Rory McIlroy effectively ruled out his chances of contending for the 152nd Open Championship after posting a disappointing opening round of 78 at Royal Troon.

Shane Lowry surged to the top of the leaderboard at five under par, taking advantage of the calmer late afternoon conditions at Royal Troon. In contrast, Rory McIlroy and Bryson DeChambeau had a rough start, with McIlroy carding a seven-over-par 78 and Woods shooting a 79.

“All I need to focus on is tomorrow and try to make the cut,” McIlroy remarked via Kieran Canning.

Rory McIlroy's struggles

Rory McIlroy reacts after hitting from the rough on the 15th hole during the first round of the Open Championship golf tournament at Royal Troon. Mandatory Credit: Jack Gruber-USA TODAY Sports
Jack Gruber-USA TODAY Sports

Rory McIlroy was even par after the first seven holes but then faltered with a double bogey on the signature par-three eighth. His attempt to escape a bunker on the Postage Stamp hole ended up with the ball returning to his feet.

“I need to go out there and play better and try to shoot something under par and at least be here for the weekend, if not try to put myself up the leaderboard a bit more and feel like I have half a chance,” McIlroy continued.

With the back nine playing downwind, McIlroy hoped to make up for his earlier mistakes. However, he drove out of bounds on the 11th hole, resulting in another double bogey. He ended the day at seven over par, trailing clubhouse leader Justin Thomas by 10 shots.

The 35-year-old, who narrowly missed out on securing his long-awaited fifth major title at last month’s US Open, 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 made a double.”

Bryson DeChambeau also didn't fare well

Bryson DeChambeau, who narrowly defeated McIlroy at Pinehurst to secure his second US Open title, also struggled in the field after shooting a 76. However, the American managed to salvage his round with a 55-foot eagle on the 16th hole.

DeChambeau's front nine of 42 featured a double bogey on the 612-yard sixth hole, where his second shot advanced only a few yards from the heavy rough before he had to hit his next shot onto the adjacent 13th fairway.

The morning conditions, marked by light rain and gusty winds of up to 23 miles per hour, created chaos for the golfers.

Justin Thomas rising to the occasion 

Despite the challenging weather, Justin Thomas managed to secure a 3-under round, bolstered by two birdies at the end of his round, allowing him to hold a strong position on the leaderboard for much of the morning.

Thomas started strong with a chip-in birdie on the par-4 second hole and added three more birdies while making just one bogey to reach the turn at 3-under 33. However, his momentum faltered on the back nine. A poorly pulled tee shot on the 12th forced him to take a penalty drop, resulting in a double-bogey. He further struggled on the 13th, where he pushed his drive into the high rough on the right, leading to another bogey.

Thomas ended his round strong, sinking birdies on the last two holes, including a 25-footer on No. 18. This finish brought him back to 3 under par, placing him one stroke ahead of Alex Noren, Nicolai Højgaard, Justin Rose, and Russell Henley.

Cameron Smith, the 2021 champion at St. Andrews, struggled with an 80. World No. 4 Ludvig Åberg also had a challenging debut British Open round, finishing with a four-over 75.