PORTRUSH, Northern Ireland — The outcome was never in doubt to just about everyone but Shane Lowry.

A year ago, he sat in the parking lot at Carnoustie and cried after missing the cut in the British Open for the fourth straight year. Even with a four-shot lead Sunday at Royal Portrush, in a raging wind and pouring rain, Lowry kept telling his caddie he was nervous and scared, worried that he would ruin a storybook ending to the first Open in Northern Ireland in 68 years.

"I suppose I didn't even know going out this morning if I was good enough to win a major," Lowry said. "And look, I'm here now, a major champion. I can't believe I'm saying it, to be honest."

The 32-year-old Irishman marks his golf ball with a green shamrock. This had nothing to do with luck.

With stout nerves and a soft touch around the greens, Lowry gave a sellout crowd what they wanted to see. He endured the worst weather of the week, held up under Sunday pressure and expectations of fans who cheered his every step, and won the British Open by six shots.

All he could think about was that walk up the final hole, and it was everything he imagined.

Even as the rain stopped, the tears began flowing.

"I can't believe this is me standing here," Lowry said has he cradled the silver claret jug. "I can't believe this is mine."

Lowry closed with a 1-over 72, the first time since 1996 the Open champion was over par in the final round, and it was no less impressive. More difficult than the rain was wind strong enough to break an umbrella. Lowry made four bogeys in the toughest stretch of Royal Portrush without losing ground.

No one from the last 12 groups broke par. No one got closer than three shots of Lowry all day.

"It was Shane's time, Shane's tournament," said Tommy Fleetwood, who closed with a 74 to finish runner-up for the second time in a major.

Thousands of fans who filled these links off the North Atlantic began to celebrate when Lowry rolled in an 8-foot birdie putt on the 15th hole to stretch his lead to six with three holes to play.