Lowry and Brown flawless as Rory McIlroy cruises through first round at Royal Troon

Shane Lowry made a flawless start to his quest for a second Open title as Rory McIlroy effectively bookended his chances of doing the same at Royal Troon.

Lowry carded five birdies in a bogey-free 66 surpassed only at 9.33pm by England's Daniel Brown, the world number 272 returning a smart 65 to take a shock lead on his Open debut.

Brown, who won his first DP World Tour title in Northern Ireland 11 months ago, took advantage of the calm conditions to get the starters going and birdie the third, fifth, 10th, 11th, 16th and 18.

It was a contrast that immediately brought to mind the 2019 Open at Royal Portrush, when Lowry opened with a 67 on his way to the Claret Jug and McIlroy's chances were beaten with a 79.

“It was great,” Lowry, who birdied the fourth, seventh, eighth, 11th and 18th, told Sky Sports.

“I started slow and hit some nice putts early on and then I started running.

“I try not to think about it [2019] more now. I putt to take the lead and I thought 'This is the first time I've led the Open in five years'.

“No matter what I do that church in Portrush will always have a special place in my heart. I love this place and I love this competition.”

Defeated Rory McIlroy had previously squandered his chances of challenging for a fifth major title after a costly hole-in-one run around the opportunity.

McIlroy was at par through seven holes before he double bogeyed the signature eighth, the Northern Irishman's first attempt to escape a postage stamp bunker back to his feet.

With the back 9 playing downwind McIlroy hoped to repair the damage, only to go out of bounds on the 11th to run up another double bogey and eventually finish seven over par, 12 shots behind Lowry.

According to statistician Justin Ray, chief data analyst at KPMG Performance Insights, 87 percent of Open winners since 1960 have been within four shots of the lead after the first round.

Asked if he could fix the group, there was a long pause before McIlroy said: “I mean, what I have to focus on tomorrow is trying to cut through.” That's all I can focus on.”

The 35-year-old, who narrowly missed out on an overdue fifth major title at the US Open last month, added: “I felt like I did well in the first half of the round and then I missed the green at Postage Stamp there again. he did twice.

“But anyway, I felt like I was in good enough shape for par from the back nine, I thought I might get those few shots, try to even shoot for par, something like that.

“Although the wind blowing at the back of the ninth helped, it was too far to the left. I was actually surprised at how difficult I was with the back nine playing. Conditions are very difficult with the wind we have not seen so far this week.

“I think when that starts to introduce different approaches and you think maybe you hit a few clubs that you haven't hit in practice. It's just one of those days where I didn't adapt well.”

Bryson DeChambeau, who ousted McIlroy at Pinehurst to win a second US Open, also found himself well short of the field after a 76, although the American holed an eagle from at least 55 meters on the 16th.

DeChambeau's front nine of 42 included a double bogey on the sixth for 612, where he managed to push his second shot a few yards out of the rough before hitting the next one on the nearby 13th fairway.

“It was a green lie and I tried to hit the 7-iron out, and I didn't get it close enough,” DeChambeau said.

“Then I tried to hit the 5 wood and it came off the left side of my clubface and it just shot left. I'm glad no one was hurt.”

Thomas set the clubhouse target at three under thanks to birdies on the 17th and 18th, the two-time winner's 68 representing a 14-shot improvement on his opening round at Hoylake last year.

“I couldn't even tell you what I was thinking and what it was like at the time,” said Thomas when asked to compare the two rounds.

“I'm worried about how I'm doing now, and I'm very happy with my game and I know that things continue to work out. I have to keep trying to play well.”

Sweden's Alex Noren, who secured his place in the field with a tie for 10th place at the Scottish Open on Sunday, came out alongside American Russell Henley and Ryder Cup teammates Justin Rose and Nicolai Hojgaard.

Rose, who had to go through a 36-hole qualifier to reach Troon, carded two birdies and 16 pars in his bogey-free 69.