Bob Harig and Michael Collins demonstrate the tight quarters at The Open in keeping with old traditions. (1:19)

PORTRUSH, Northern Ireland -- Rory McIlroy started his opening round of the 148th Open Championship with a quadruple-bogey on the first hole and finished with a triple-bogey on the 18th at Royal Portrush Golf Club.

In between, it was an agonizingly frustrating day for the four-time major winner in the first Open Championship played in his native Northern Ireland in 68 years.

McIlroy finished at 8-over 79 after 18 holes, which was 12 shots behind leader Shane Lowry after the early wave on Thursday.

"I guess when you play your first and last in a combined 7 over par, you're sort of starting on the back foot," McIlroy said. "Obviously, I got off to a rough start. ... I felt like I showed some good resiliency after that. I think I played the next 12 or 13 holes in 2 under par, and then really what I'm disappointed about is that I undid all that great work the last few holes."

McIlroy, the betting favorite to win The Open, hit his first tee shot on the par-4, 421-yard 1st hole out of bounds. His ball ended up hitting a woman and cracking the screen of a cellphone in her pocket.

"The ball sort of just got going left on the wind on the first hole," McIlroy said. "I actually hit the ball out of bounds right in the practice round [on Wednesday], so that might have been in my head a little bit, not wanting to leak it out to the right."

After a one-stroke penalty, McIlroy hit his second tee shot into the deep rough on the left side of the fairway. His fourth shot was low and ended up in even thicker rough on the left side of the green. He was forced to take an unplayable lie near the green.

Then he made a great pitch shot to about five feet and two-putted for 8.

Northern Ireland's Rory McIlroy looks for his ball in the long rough on the first hole during the first round of The Open at Royal Portrush. Associated Press

According to ESPN Stats & Information, it's the first time McIlroy started a major championship with a double-bogey or worse since the 2012 Masters, when he opened with a double-bogey. It's only his second quadruple-bogey in a major (he had one on the 11th hole in the final round of the 2013 U.S. Open at Merion) and only the fourth in his PGA Tour career.

No major winner in the past 20 years started a tournament with worse than a double-bogey.

McIlroy recovered and made two birdies and zero bogeys in the final eight holes of the front nine, and then he had par on the first six holes of the back. But then things fell apart in the final three holes.

On the par-3 16th hole, aptly named "Calamity Corner," McIlroy needed four putts for a double-bogey 5. He missed a 4-footer for par and then slapped and missed a 1-footer for bogey.

"I lost concentration after the missed par putt on 16 and missed a short one there," he said.

On the par-4 18th hole, McIlroy hit his tee shot into the rough and couldn't get his second shot back to the fairway. He ended up with a triple-bogey 7.

"On 18, I hit a tee shot that I knew wasn't going to be in the fairway, but I didn't think it was going to be quite as bad as it was," McIlroy said. "I tried to hack it out back to the fairway, but it didn't come out of the lie. It was a pretty tough hole anyway."

It was a disappointing opening round for McIlroy, 30, who grew up in nearby Holywood and set the Royal Portrush course record with a 61 when he was 16.

It was the fourth time since 2016 that he shot 77 or worse in a major, which is tied with Jhonattan Vegas and Mark O'Meara for the most by any PGA Tour player during that span.

"It was obviously a disappointing day," McIlroy said. "I didn't put it in the fairway enough to play. I kept saying that in the press conference [Wednesday], 'You need to put the ball in the fairway here if you want to do well,' and I didn't do that enough today to create enough scoring opportunities."