Patience key as MacIntyre stays in hunt for Open title

"Then I knew I just had to try and take advantage of the par fives. It's getting so fast, the fairways are running so fast that it doesn't matter what club you're hitting - any bunkers are in play.

"I probably hit more drivers than I thought I was going to, but you have to pick the shot. It's got to be high, low, left to right, right to left - it doesn't matter.

"You've just got to pick the right shot to land it softer. It was free-running golf."

MacIntyre had to wait until the 14th hole for his first birdie of the day after turning in one over par.

The Scot admitted the round could easily have slipped away before he finished on four under for the championship.

"It was a difficult putt on 14. I hadn't holed any real putts, but it was a great putt. It was a real mover, it was moving a lot down the hill.

"Then it was just about not making a mistake. I missed the green on the left, pin high, on 16. I thought that was a bit of a mistake, but you've got to trust the short game because you can deal with any shot. It was a lovely bump-and-run up there.

"It's a great spot to be in. I couldn't ask for a better position after the start I had today. It was lovely to grind out the round, finish one under for the day and go again tomorrow."

Earlier in the day, Herbert and Sam Burns matched the lowest round ever recorded at a men's major by carding eight-under-par 62s.

MacIntyre said he was not surprised to see the world's best players taking advantage of the scoring opportunities.

"Unbelievable," he added. "I said it out there to some of the boys, it does not matter.

"They keep worrying about score to par and how hard the golf course is, but these guys are the best in the world.

"If they're on their game, they will shoot the lights out. I thought one-under-par was a hell of an effort - eight under par is outrageous."