"I got off to a great start," McIlroy told reporters. "Was a couple under through nine and then gave those shots away on two of the easier holes on the course, 11 and 15. But it was nice to at least get one of them back on 18 there."

The conditions were much harder on Friday with strong winds blowing around the course.

"It played really, really tough," the Northern Irishman said. "10-under par is unbelievably impressive out there. But after two days I'm actually pretty happy with my two days' work."

McIlroy, who won the Open last time it was played at Hoylake in 2014, is not planning to change his approach over the weekend.

"I don't think I have to do anything differently," he said. "I'm hitting the ball well from tee to green. I've missed a couple of chances on the greens. The wind got me today. It's hard sometimes in two minds whether to play the wind or not to play the wind."

The Northern Irishman is not expecting low scoring from the late starters in the second round.

"I might be nine back, but I don't think there's going to be a ton of players between me and the lead going into the weekend," he said.

"I think more of the same, patience, hitting fairways, hitting greens, making good decisions. If I can do that and have a good attitude towards it all, that's what I expect of myself."