PORTRUSH, Northern Ireland — The moment that surprised Rory McIlroy the most when he played the 2019 Britidh Open at Royal Portrush—the first Open held in his home country of Northern Ireland since 1951—was the ovation on the first tee.

In the lineage of golf courses, Royal Portrush isn't in the same stratosphere as St. Andrews or Augusta National or Pebble Beach. But to Rory McIlroy, it's special.