PORTRUSH, Northern Ireland — An emotional opening shot by Darren Clarke. A shocking one by Rory McIlroy.

Tiger Woods had his worst score to start a British Open. Brooks Koepka quickly got into contention again.

Emiliano Grillo made a 1. David Duval made a 14.

The Open returned to Royal Portrush after a 68-year absence and made up for lost time with an unusual amount of theater Thursday. When more than 15 hours of golf before a robust, sellout crowd finally ended, J.B. Holmes was atop the leaderboard at a major for the first time in 11 years.

Even that might have been fitting. The big hitter from a small town in Kentucky had his first taste of links golf at Royal Portrush during a college trip, and he recalled how the caddies kept giving him the wrong lines off the tee because they had never seen anyone hit it that far.

Holmes drove the downwind 374-yard fifth hole to 12 feet for a two-putt birdie, and he ended with a 5-iron into the wind to 15 feet for a final birdie and a 5-under 66.

“You just have to accept the conditions over here and not get too greedy,” Holmes said.

He had a one-shot lead over Shane Lowry of Ireland, who didn’t have the level of expectations or the connection to Royal Portrush like McIlroy, Clarke or native son Graeme McDowell, all of whom grew up in Northern Ireland and never imagined golf’s oldest championship returning to their tiny country.