HOYLAKE, England — Rory McIlroy put up a dazzling score on the opening day of the British Open.

Yawn.

Let’s see if he can do it again.

McIlroy heads into Day 2 at Royal Liverpool with a one-shot lead after a 6-under 66, a familiar position that either sets him up for a good run at the claret jug — or another dose of second-round failure.

This year, McIlroy has started a couple of tournaments with 63s and another with a 64, but wasn’t able to win any of them. For some reason, he’s had a serious case of the yips in the second round, putting up a cumulative score of 15-over par compared with 55 under for the opening round, and 39 under on the weekend.

Talk about Freaky Friday.

“It’s not like I’ve shot good scores in first rounds and haven’t backed them up before,” McIlroy said. “I’m used to doing that. I just haven’t done it recently.

“Hopefully,” he added, “it’s just one of those things and I’m able to turn it around.”

As with any British Open, the weather will likely play a major role.

On Thursday, McIlroy and the other morning starters benefited from pristine conditions — sunny and mild, with only a hint of a breeze off the Irish Sea. But heavy rain was in the forecast for today, which could make things a lot more interesting.

“We had perfect scoring conditions,” said McIlroy, who didn’t make a bogey and birdied three of the four par-5s.